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Huang HL, Cheng N, Zhou CX, Liang J. Megalin-targeted acetylcysteine polymeric prodrug ameliorates ischemia-reperfusion-induced acute kidney injury. Heliyon 2024; 10:e30947. [PMID: 38770316 PMCID: PMC11103533 DOI: 10.1016/j.heliyon.2024.e30947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 05/08/2024] [Accepted: 05/08/2024] [Indexed: 05/22/2024] Open
Abstract
Acute kidney injury (AKI), a condition associated with reactive oxygen species (ROS), causes high mortality in clinics annually. Active targeted antioxidative therapy is emerging as a novel strategy for AKI treatment. In this study, we developed a polymeric prodrug that targets the highly expressed Megalin receptor on proximal tubule cells, enabling direct delivery of N-Acetylcysteine (NAC) for the treatment of ischemia reperfusion injury (IRI)-induced AKI. We conjugated NAC with low molecular weight chitosan (LMWC), a biocompatible and biodegradable polymer consisting of glucosamine and N-acetylglucosamine, to enhance its internalization by tubular epithelial cells. Moreover, we further conjugated triphenylphosphonium (TPP), a lipophilic cation with a delocalized positive charge, to low molecular weight chitosan-NAC in order to enhance the distribution of NAC in mitochondria. Our study confirmed that triphenylphosphonium-low molecular weight chitosan-NAC (TLN) exhibits remarkable therapeutic effects on IRI-AKI mice. This was evidenced by improvements in renal function, reduction in oxidative stress, mitigation of pathological progress, and decreased levels of kidney injury molecule-1. These findings suggested that the polymeric prodrug TLN holds promising potential for IRI-AKI treatment.
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Affiliation(s)
- Hao-Le Huang
- Department of Nephrology, the Affiliated People's Hospital of Ningbo University, Ningbo, 315040, China
| | - Na Cheng
- Department of Nephrology, the Affiliated People's Hospital of Ningbo University, Ningbo, 315040, China
| | - Can-Xin Zhou
- Department of Nephrology, the Affiliated People's Hospital of Ningbo University, Ningbo, 315040, China
| | - Jing Liang
- Department of Pharmacy, Zhejiang Hospital, Hangzhou, 310013, China
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2
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Goto S, Tsutsumi A, Lee Y, Hosojima M, Kabasawa H, Komochi K, Nagatoishi S, Takemoto K, Tsumoto K, Nishizawa T, Kikkawa M, Saito A. Cryo-EM structures elucidate the multiligand receptor nature of megalin. Proc Natl Acad Sci U S A 2024; 121:e2318859121. [PMID: 38771880 PMCID: PMC11145282 DOI: 10.1073/pnas.2318859121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 04/19/2024] [Indexed: 05/23/2024] Open
Abstract
Megalin (low-density lipoprotein receptor-related protein 2) is a giant glycoprotein of about 600 kDa, mediating the endocytosis of more than 60 ligands, including those of proteins, peptides, and drug compounds [S. Goto, M. Hosojima, H. Kabasawa, A. Saito, Int. J. Biochem. Cell Biol. 157, 106393 (2023)]. It is expressed predominantly in renal proximal tubule epithelial cells, as well as in the brain, lungs, eyes, inner ear, thyroid gland, and placenta. Megalin is also known to mediate the endocytosis of toxic compounds, particularly those that cause renal and hearing disorders [Y. Hori et al., J. Am. Soc. Nephrol. 28, 1783-1791 (2017)]. Genetic megalin deficiency causes Donnai-Barrow syndrome/facio-oculo-acoustico-renal syndrome in humans. However, it is not known how megalin interacts with such a wide variety of ligands and plays pathological roles in various organs. In this study, we elucidated the dimeric architecture of megalin, purified from rat kidneys, using cryoelectron microscopy. The maps revealed the densities of endogenous ligands bound to various regions throughout the dimer, elucidating the multiligand receptor nature of megalin. We also determined the structure of megalin in complex with receptor-associated protein, a molecular chaperone for megalin. The results will facilitate further studies on the pathophysiology of megalin-dependent multiligand endocytic pathways in multiple organs and will also be useful for the development of megalin-targeted drugs for renal and hearing disorders, Alzheimer's disease [B. V. Zlokovic et al., Proc. Natl. Acad. Sci. U.S.A. 93, 4229-4234 (1996)], and other illnesses.
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Affiliation(s)
- Sawako Goto
- Department of Applied Molecular Medicine, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
| | - Akihisa Tsutsumi
- Department of Cell Biology and Anatomy, Graduate School of Medicine, The University of Tokyo, Tokyo113-0033, Japan
| | - Yongchan Lee
- Department of the Biological Membrane Dynamics, Graduate School of Medical Life Science, Yokohama City University, Yokohama230-0045, Japan
| | - Michihiro Hosojima
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
| | - Hideyuki Kabasawa
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
| | - Koichi Komochi
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
| | - Satoru Nagatoishi
- Medical Device Development and Regulation Research Center, School of Engineering, The University of Tokyo, Tokyo113-8656, Japan
| | - Kazuya Takemoto
- Department of Applied Molecular Medicine, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
| | - Kouhei Tsumoto
- Department of Bioengineering, School of Engineering, The University of Tokyo, Tokyo113-8656, Japan
| | - Tomohiro Nishizawa
- Department of the Biological Membrane Dynamics, Graduate School of Medical Life Science, Yokohama City University, Yokohama230-0045, Japan
| | - Masahide Kikkawa
- Department of Cell Biology and Anatomy, Graduate School of Medicine, The University of Tokyo, Tokyo113-0033, Japan
| | - Akihiko Saito
- Department of Applied Molecular Medicine, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata City951-8510, Japan
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3
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Fendler A, Stephan C, Ralla B, Jung K. Discordant Health Implications and Molecular Mechanisms of Vitamin D in Clinical and Preclinical Studies of Prostate Cancer: A Critical Appraisal of the Literature Data. Int J Mol Sci 2024; 25:5286. [PMID: 38791324 PMCID: PMC11120741 DOI: 10.3390/ijms25105286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Clinical and preclinical studies have provided conflicting data on the postulated beneficial effects of vitamin D in patients with prostate cancer. In this opinion piece, we discuss reasons for discrepancies between preclinical and clinical vitamin D studies. Different criteria have been used as evidence for the key roles of vitamin D. Clinical studies report integrative cancer outcome criteria such as incidence and mortality in relation to vitamin D status over time. In contrast, preclinical vitamin D studies report molecular and cellular changes resulting from treatment with the biologically active vitamin D metabolite, 1,25-dihydroxyvitamin D3 (calcitriol) in tissues. However, these reported changes in preclinical in vitro studies are often the result of treatment with biologically irrelevant high calcitriol concentrations. In typical experiments, the used calcitriol concentrations exceed the calcitriol concentrations in normal and malignant prostate tissue by 100 to 1000 times. This raises reasonable concerns regarding the postulated biological effects and mechanisms of these preclinical vitamin D approaches in relation to clinical relevance. This is not restricted to prostate cancer, as detailed data regarding the tissue-specific concentrations of vitamin D metabolites are currently lacking. The application of unnaturally high concentrations of calcitriol in preclinical studies appears to be a major reason why the results of preclinical in vitro studies hardly match up with outcomes of vitamin D-related clinical studies. Regarding future studies addressing these concerns, we suggest establishing reference ranges of tissue-specific vitamin D metabolites within various cancer entities, carrying out model studies on human cancer cells and patient-derived organoids with biologically relevant calcitriol concentrations, and lastly improving the design of vitamin D clinical trials where results from preclinical studies guide the protocols and endpoints within these trials.
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Affiliation(s)
- Annika Fendler
- Department of Urology, Charité—Universitätsmedizin Berlin, 10117 Berlin, Germany; (A.F.); (B.R.)
- Berlin Institute for Urologic Research, 10115 Berlin, Germany
| | - Carsten Stephan
- Department of Urology, Charité—Universitätsmedizin Berlin, 10117 Berlin, Germany; (A.F.); (B.R.)
- Berlin Institute for Urologic Research, 10115 Berlin, Germany
| | - Bernhard Ralla
- Department of Urology, Charité—Universitätsmedizin Berlin, 10117 Berlin, Germany; (A.F.); (B.R.)
| | - Klaus Jung
- Department of Urology, Charité—Universitätsmedizin Berlin, 10117 Berlin, Germany; (A.F.); (B.R.)
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4
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Ruiz MA, Zhang X, Mansilla MA, Zahr RS, Thomas CP, Smith RJ, Gordeuk VR, Saraf SL. Prevalence of kidney health genetic variants in adults with sickle cell nephropathy. Br J Haematol 2024. [PMID: 38735682 DOI: 10.1111/bjh.19525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 04/30/2024] [Indexed: 05/14/2024]
Abstract
The pathophysiology and genetic risk for sickle cell disease (SCD)-related chronic kidney disease (CKD) are not well understood. In 70 adults with SCD-related CKD and without APOL1 inherited in a high-risk pattern, 24 (34%) had pathogenic variants in candidate genes using KidneySeq™. A moderate impact INF2 variant was observed in 20 (29%) patients and those with 3 versus 0-2 pathogenic or moderate impact glomerular genetic variants had higher albuminuria and lower estimated glomerular filtration rate (adjusted p ≤ 0.015). Using a panel of preselected genes implicated in kidney health, we observed several variants in people with sickle cell nephropathy.
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Affiliation(s)
- Maria Armila Ruiz
- Division of Hematology and Oncology, Sickle Cell Center, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Xu Zhang
- Division of Hematology and Oncology, Sickle Cell Center, University of Illinois at Chicago, Chicago, Illinois, USA
| | - M Adela Mansilla
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Rima S Zahr
- Division of Pediatric Nephrology and Hypertension, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Christie P Thomas
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Richard J Smith
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Victor R Gordeuk
- Division of Hematology and Oncology, Sickle Cell Center, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Santosh L Saraf
- Division of Hematology and Oncology, Sickle Cell Center, University of Illinois at Chicago, Chicago, Illinois, USA
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Lackner EM, Cowan IA, Long KR, Weisz OA, Shipman KE. Fluid Shear Stress-Induced Changes in Megalin Trafficking Enhance Endocytic Capacity in Proximal Tubule Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.22.581213. [PMID: 38562767 PMCID: PMC10983855 DOI: 10.1101/2024.02.22.581213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Proximal tubule (PT) cells maintain a high-capacity apical endocytic pathway to recover essentially all proteins that escape the glomerular filtration barrier. The multiligand receptors megalin and cubilin play pivotal roles in the endocytic uptake of normally filtered proteins in PT cells but also contribute to the uptake of nephrotoxic drugs, including aminoglycosides. We previously demonstrated that opossum kidney (OK) cells cultured under continuous fluid shear stress (FSS) are superior to cells cultured under static conditions in recapitulating essential functional properties of PT cells in vivo. To identify drivers of the high-capacity, efficient endocytic pathway in the PT, we compared FSS-cultured OK cells with less endocytically active static-cultured OK cells. Megalin and cubilin expression are increased, and endocytic uptake of albumin in FSS-cultured cells is >5-fold higher compared with cells cultured under static conditions. To understand how differences in receptor expression, distribution, and trafficking rates contribute to increased uptake, we used biochemical, morphological, and mathematical modeling approaches to compare megalin traffic in FSS- versus static-cultured OK cells. Our model predicts that culturing cells under FSS increases the rates of all steps in megalin trafficking. Importantly, the model explains why, despite seemingly counterintuitive observations (a reduced fraction of megalin at the cell surface, higher colocalization with lysosomes, and a shorter half-life of surface-tagged megalin in FSS-cultured cells), uptake of albumin is dramatically increased compared with static-grown cells. We also show that FSS-cultured OK cells more accurately exhibit the mechanisms that mediate uptake of nephrotoxic drugs in vivo compared with static-grown cells. This culture model thus provides a useful platform to understand drug uptake mechanisms, with implications for developing interventions in nephrotoxic injury prevention.
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Affiliation(s)
- Emily M. Lackner
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Isabella A. Cowan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kimberly R. Long
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Ora A. Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Katherine E. Shipman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Jiang J, Li T, Wang E, Zhang Y, Han J, Tan L, Li X, Fan Y, Wu Y, Chen Q, Jin J. Polybrominated diphenyl ethers in dust, hair and urine: Exposure, excretion. CHEMOSPHERE 2024; 352:141380. [PMID: 38368958 DOI: 10.1016/j.chemosphere.2024.141380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/21/2024] [Accepted: 02/02/2024] [Indexed: 02/20/2024]
Abstract
Polybrominated diphenyl ethers (PBDEs) have been detected in various environmental media and human tissues. PBDEs concentrations in dust from college buildings and homes and in paired hair and urine samples from students were determined. This is of great significance to explore the accumulation and excretion patterns of PBDEs in the human body. The median PBDEs concentrations in the dust (College: 84.59 ng/g; Home: 170.32 ng/g) and hair (undergraduate: 6.16 ng/g; Home: 3.25 ng/g) samples were generally lower than were found in the majority of previous studies. The PBDEs concentrations in the hair and urine samples were subjected to principal component analysis, and the results combined with the PBDEs detection rates confirmed that hair is a useful non-invasive sampling medium for assessing PBDEs exposure and the risks posed. Body mass indices (BMIs) were used to divide students who had not been exposed to large amounts of PBDEs into groups. Body fat percentage is an important factor affecting the accumulation of PBDE in the human body. Environmental factors were found to affect the PBDEs concentrations in the hair and urine samples less for normal-weight students (BMI≤24) than overweight students (BMI>24). Short-term environmental changes to more readily affect the PBDEs concentrations in the tissues of the normal-weight than overweight students. PBDEs with seven or more bromine substituents were found not to be readily excreted in urine. Performing molecular docking simulations of the binding of isomers BDE-99 and BDE-100 to megalin. The binding energy was higher for BDE-100 and megalin than for BDE-99 and megalin, meaning BDE-99 would be more readily excreted than BDE-100.
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Affiliation(s)
- Junjie Jiang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Tianwei Li
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Erde Wang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Yan Zhang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Jiali Han
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Linli Tan
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Xiang Li
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Yuhao Fan
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Ye Wu
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Qianhui Chen
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.
| | - Jun Jin
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China; Engineering Research Center of Food Environment and Public Health, Beijing, 100081, China.
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Kuwata N, Mukohda H, Uchida H, Takamatsu R, Binici MM, Yamada T, Sugiyama T. Renal Endocytic Regulation of Vitamin D Metabolism during Maturation and Aging in Laying Hens. Animals (Basel) 2024; 14:502. [PMID: 38338146 PMCID: PMC10854989 DOI: 10.3390/ani14030502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 01/27/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024] Open
Abstract
Egg-laying hens undergo a specific and dramatic calcium metabolism to lay eggs with eggshells composed of calcium carbonate. Calcium metabolism is mainly regulated by vitamin D3. Although vitamin D3 metabolism is closely related to the deterioration of eggshell quality associated with aging and heat stress, the details of the mechanisms regulating vitamin D3 metabolism are not clear. In mammals, the vitamin D3 metabolite (25(OH)D3) produced in the liver binds to the vitamin binding protein (DBP), is subsequently taken up by renal proximal tubular cells via the endocytic receptors megalin (Meg) and cubilin (CUB), and is metabolized to 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). Therefore, the present study aimed to examine the expression and localization of Meg and CUB in the kidneys of immature chicks and mature and aged laying hens to prevent eggshell quality deterioration. As a result, we showed that as circulating 1,25(OH)2D3 concentrations increased from 156.0 ± 13.5 pg/mL to 815.5 ± 61.4 pg/mL with maturation in immature chicks, relative expression levels (arbitrary units; AU) of Meg and CUB mRNA in the kidneys of mature hens significantly increased 1.92- and 2.75-fold, respectively, compared to those in immature chicks. On the other hand, the Meg mRNA expression levels of mature hens did not change with age, while CUB mRNA expression levels (1.03 ± 0.11 AU) were significantly decreased compared to mature hens (2.75 ± 0.24 AU). Immunohistochemical observations showed that Meg and CUB proteins were localized to the apical membrane of renal proximal tubular epithelial cells in immature chicks, mature hens, and aged hens, and that DBP protein was observed as granular endosomes in the cytoplasm of proximal tubular cells from the apical membrane to the cell nucleus. Especially in mature hens, the endosomes were larger and more numerous than those in immature chicks. In contrast, in aged hens, DBP-containing endosomes were smaller and limited to the apical cytoplasm. These results indicate that with maturation, the expression of Meg and CUB is promoted in the renal proximal tubules of laying hens, facilitating the uptake of the 25(OH)D3-DBP complex and its conversion to 1,25(OH)2D3, and regulating calcium metabolism in eggshell formation. On the other hand, it is suggested that the age-related decrease in CUB expression suppresses the uptake of the 25(OH)D3-DBP complex in the kidney, resulting in a deterioration of eggshell quality.
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Affiliation(s)
- Nami Kuwata
- Graduate School of Science and Technology, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan
| | - Hatsune Mukohda
- Graduate School of Science and Technology, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan
| | - Hiroto Uchida
- Graduate School of Science and Technology, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan
| | - Ryo Takamatsu
- Graduate School of Science and Technology, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan
| | - Muhammet Mustafa Binici
- Graduate School of Science and Technology, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan
| | - Takahisa Yamada
- Department of Animal Science, Faculty of Agriculture, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan;
| | - Toshie Sugiyama
- Department of Animal Science, Faculty of Agriculture, Niigata University, 2-8050 Ikarashi, Nishi-ku, Niigata 9502181, Japan;
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De Souza Cordeiro LM, Atkinson KC, Aivazian A, Joyce PF, Jia F, Mascioni A. Electrostatic properties of human germlines and biodistribution of small biologics. MAbs 2024; 16:2311991. [PMID: 38334129 PMCID: PMC10860348 DOI: 10.1080/19420862.2024.2311991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/25/2024] [Indexed: 02/10/2024] Open
Abstract
Off-target biodistribution of biologics bears important toxicological consequences. Antibody fragments intended for use as vectors of cytotoxic payloads (e.g. antibody-drug conjugates, radiotherapy) can accumulate at clearance organs like kidneys and liver, where they can cause dose-limiting toxicities. Renal and hepatic uptakes are known to be affected by protein electrostatics, which promote protein internalization through pinocytosis. Using minibodies as a model of an antibody fragment lacking FcRn recycling, we compared the biodistributions of leads with different degrees of accumulation at the kidney and liver. We identified a positive electrostatic patch highly conserved in a germline family very commonly used in the humanization of approved biologics. Neutralization of this patch led to a drastic reduction in the kidney uptake, leading to a biodistribution more favorable to the delivery of highly cytotoxic payloads. Next, we conducted a high throughput study of the electrostatic properties for all combinations of VH and VL germlines. This analysis shows how different VH/VL combinations exhibit varying tendencies to create electrostatic patches, resulting in Fv variants with different isoelectric points. Our work emphasizes the importance of carefully selecting germlines for humanization with optimal electrostatic properties in order to control the unspecific tissue uptake of low molecular weight biologics.
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Affiliation(s)
| | | | - Argin Aivazian
- Preclinical discovery, ImaginAb, Inc, Inglewood, CA, USA
| | | | - Fang Jia
- Preclinical discovery, ImaginAb, Inc, Inglewood, CA, USA
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Chen X, Dai W, Li H, Yan Z, Liu Z, He L. Targeted drug delivery strategy: a bridge to the therapy of diabetic kidney disease. Drug Deliv 2023; 30:2160518. [PMID: 36576203 PMCID: PMC9809356 DOI: 10.1080/10717544.2022.2160518] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Diabetic kidney disease (DKD) is the main complication in diabetes mellitus (DM) and the main cause of end-stage kidney disease worldwide. However, sodium glucose cotransporter 2 (SGLT2) inhibition, glucagon-like peptide-1 (GLP-1) receptor agonist, mineralocorticoid receptor antagonists and endothelin receptor A inhibition have yielded promising effects in DKD, a great part of patients inevitably continue to progress to uremia. Newly effective therapeutic options are urgently needed to postpone DKD progression. Recently, accumulating evidence suggests that targeted drug delivery strategies, such as macromolecular carriers, nanoparticles, liposomes and so on, can enhance the drug efficacy and reduce the undesired side effects, which will be a milestone treatment in the management of DKD. The aim of this article is to summarize the current knowledge of targeted drug delivery strategies and select the optimal renal targeting strategy to provide new therapies for DKD.
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Affiliation(s)
- Xian Chen
- Department of Nephrology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China
| | - Wenni Dai
- Department of Nephrology, Hunan Key Lab of Kidney Disease and Blood Purification, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China
| | - Hao Li
- Department of Nephrology, Hunan Key Lab of Kidney Disease and Blood Purification, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China
| | - Zhe Yan
- Department of Nephrology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China
| | - Zhiwen Liu
- Department of Nephrology, Hunan Key Lab of Kidney Disease and Blood Purification, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China
| | - Liyu He
- Department of Nephrology, Hunan Key Lab of Kidney Disease and Blood Purification, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China,CONTACT Liyu He Department of Nephrology, Hunan Key Lab of Kidney Disease and Blood Purification, The Second Xiangya Hospital, Central South University, 139 Renmin Road, Changsha, Hunan410011, People’s Republic of China
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Thévenod F, Herbrechter R, Schlabs C, Pethe A, Lee WK, Wolff NA, Roussa E. Role of the SLC22A17/lipocalin-2 receptor in renal endocytosis of proteins/metalloproteins: a focus on iron- and cadmium-binding proteins. Am J Physiol Renal Physiol 2023; 325:F564-F577. [PMID: 37589051 DOI: 10.1152/ajprenal.00020.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 08/15/2023] [Accepted: 08/15/2023] [Indexed: 08/18/2023] Open
Abstract
The transmembrane protein SLC22A17 [or the neutrophil gelatinase-associated lipocalin/lipocalin-2 (LCN2)/24p3 receptor] is an atypical member of the SLC22 family of organic anion and cation transporters: it does not carry typical substrates of SLC22 transporters but mediates receptor-mediated endocytosis (RME) of LCN2. One important task of the kidney is the prevention of urinary loss of proteins filtered by the glomerulus by bulk reabsorption of multiple ligands via megalin:cubilin:amnionless-mediated endocytosis in the proximal tubule (PT). Accordingly, overflow, glomerular, or PT damage, as in Fanconi syndrome, results in proteinuria. Strikingly, up to 20% of filtered proteins escape the PT under physiological conditions and are reabsorbed by the distal nephron. The renal distal tubule and collecting duct express SLC22A17, which mediates RME of filtered proteins that evade the PT but with limited capacity to prevent proteinuria under pathological conditions. The kidney also prevents excretion of filtered essential and nonessential transition metals, such as iron or cadmium, respectively, that are largely bound to proteins with high affinity, e.g., LCN2, transferrin, or metallothionein, or low affinity, e.g., microglobulins or albumin. Hence, increased uptake of transition metals may cause nephrotoxicity. Here, we assess the literature on SLC22A17 structure, topology, tissue distribution, regulation, and assumed functions, emphasizing renal SLC22A17, which has relevance for physiology, pathology, and nephrotoxicity due to the accumulation of proteins complexed with transition metals, e.g., cadmium or iron. Other putative renal functions of SLC22A17, such as its contribution to osmotic stress adaptation, protection against urinary tract infection, or renal carcinogenesis, are discussed.
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Affiliation(s)
- Frank Thévenod
- Institute for Physiology, Pathophysiology and Toxicology, Center for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany
- Physiology and Pathophysiology of Cells and Membranes, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Robin Herbrechter
- Institute for Physiology, Pathophysiology and Toxicology, Center for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany
| | - Carolin Schlabs
- Institute for Physiology, Pathophysiology and Toxicology, Center for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany
| | - Abhishek Pethe
- Department of Molecular Embryology, Faculty of Medicine, Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg im Breisgau, Germany
| | - Wing-Kee Lee
- Physiology and Pathophysiology of Cells and Membranes, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Natascha A Wolff
- Institute for Physiology, Pathophysiology and Toxicology, Center for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany
| | - Eleni Roussa
- Department of Molecular Embryology, Faculty of Medicine, Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg im Breisgau, Germany
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11
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Long KR, Rbaibi Y, Kashlan OB, Weisz OA. Receptor-associated protein impairs ligand binding to megalin and megalin-dependent endocytic flux in proximal tubule cells. Am J Physiol Renal Physiol 2023; 325:F457-F464. [PMID: 37534387 DOI: 10.1152/ajprenal.00165.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/11/2023] [Accepted: 07/31/2023] [Indexed: 08/04/2023] Open
Abstract
Proximal tubule (PT) cells retrieve albumin and a broad array of other ligands from the glomerular ultrafiltrate. Efficient uptake of albumin requires PT expression of both megalin and cubilin receptors. Although most proteins engage cubilin selectively, megalin is required to maintain robust flux through the apical endocytic pathway. Receptor-associated protein (RAP) is a chaperone that directs megalin to the cell surface, and recombinant RAP dramatically inhibits the uptake of numerous megalin and cubilin ligands. The mechanism by which this occurs has been suggested to involve competitive inhibition of ligand binding and/or conformational changes in megalin that prevent interaction with ligands and/or with cubilin. To discriminate between these possibilities, we determined the effect of RAP on endocytosis of albumin, which binds to cubilin and megalin receptors with high and low affinity, respectively. Uptake was quantified in opossum kidney (OK) cells and in megalin or cubilin (Cubn) knockout (KO) clones. Surprisingly, RAP inhibited fluid-phase uptake in addition to receptor-mediated uptake in OK cells and Cubn KO cells but had no effect on endocytosis when megalin was absent. The apparent Ki for RAP inhibition of albumin uptake was 10-fold higher in Cubn KO cells compared with parental OK cells. We conclude that in addition to its predicted high-affinity competition for ligand binding to megalin, the primary effect of RAP on PT cell endocytosis is to globally dampen megalin-dependent endocytic flux. Our data explain the complex effects of RAP on binding and uptake of filtered proteins and reveal a novel role in modulating endocytosis in PT cells.NEW & NOTEWORTHY Receptor-associated protein inhibits binding and uptake of all known endogenous ligands by megalin and cubilin receptors via unknown mechanism(s). Here, we took advantage of recently generated knockout cell lines to dissect the effect of this protein on megalin- and cubilin-mediated endocytosis. Our study reveals a novel role for receptor-associated protein in blocking megalin-stimulated endocytic uptake of fluid-phase markers and receptor-bound ligands in proximal tubule cells in addition to its direct effect on ligand binding to megalin receptors.
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Affiliation(s)
- Kimberly R Long
- Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Youssef Rbaibi
- Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Ossama B Kashlan
- Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Ora A Weisz
- Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
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12
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Chen M, Gu X. Emerging roles of proximal tubular endocytosis in renal fibrosis. Front Cell Dev Biol 2023; 11:1235716. [PMID: 37799275 PMCID: PMC10547866 DOI: 10.3389/fcell.2023.1235716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 09/11/2023] [Indexed: 10/07/2023] Open
Abstract
Endocytosis is a crucial component of many pathological conditions. The proximal tubules are responsible for reabsorbing the majority of filtered water and glucose, as well as all the proteins filtered through the glomerular barrier via endocytosis, indicating an essential role in kidney diseases. Genetic mutations or acquired insults could affect the proximal tubule endocytosis processes, by disturbing or overstressing the endolysosomal system and subsequently activating different pathways, orchestrating renal fibrosis. This paper will review recent studies on proximal tubular endocytosis affected by other diseases and factors. Endocytosis plays a vital role in the development of renal fibrosis, and renal fibrosis could also, in turn, affect tubular endocytosis.
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Affiliation(s)
- Min Chen
- Department of Nephrology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xiangchen Gu
- Department of Nephrology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Medicine, Shanghai Hospital of Civil Aviation Administration of China, Shanghai, China
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13
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Li Z, Fan X, Fan J, Zhang W, Liu J, Liu B, Zhang H. Delivering drugs to tubular cells and organelles: the application of nanodrugs in acute kidney injury. Nanomedicine (Lond) 2023; 18:1477-1493. [PMID: 37721160 DOI: 10.2217/nnm-2023-0200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023] Open
Abstract
Acute kidney injury (AKI) is a common clinical syndrome with limited treatment options and high mortality rates. Proximal tubular epithelial cells (PTECs) play a key role in AKI progression. Subcellular dysfunctions, including mitochondrial, nuclear, endoplasmic reticulum and lysosomal dysfunctions, are extensively studied in PTECs. These studies have led to the development of potential therapeutic drugs. However, clinical development of those drugs faces challenges such as low solubility, short circulation time and severe systemic side effects. Nanotechnology provides a promising solution by improving drug properties through nanocrystallization and enabling targeted delivery to specific sites. This review summarizes advancements and limitations of nanoparticle-based drug-delivery systems in targeting PTECs and subcellular organelles, particularly mitochondria, for AKI treatment.
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Affiliation(s)
- Zhi Li
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, 410013, China
- The Critical Kidney Disease Research Center of Central South University, Changsha, 410013, China
| | - Xiao Fan
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, 410013, China
- The Critical Kidney Disease Research Center of Central South University, Changsha, 410013, China
| | - Jialong Fan
- College of Biology, Hunan University, Changsha, 410082, China
| | - Wei Zhang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, 410013, China
- The Critical Kidney Disease Research Center of Central South University, Changsha, 410013, China
| | - Jun Liu
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, 410013, China
- The Critical Kidney Disease Research Center of Central South University, Changsha, 410013, China
| | - Bin Liu
- College of Biology, Hunan University, Changsha, 410082, China
- Department of Physiology & Pathophysiology, NHC Key Laboratory of Metabolic Cardiovascular Diseases Research, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, 750004, China
| | - Hao Zhang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, 410013, China
- The Critical Kidney Disease Research Center of Central South University, Changsha, 410013, China
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14
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Li H, Dai W, Xiao L, Sun L, He L. Biopolymer-Based Nanosystems: Potential Novel Carriers for Kidney Drug Delivery. Pharmaceutics 2023; 15:2150. [PMID: 37631364 PMCID: PMC10459991 DOI: 10.3390/pharmaceutics15082150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Kidney disease has become a serious public health problem throughout the world, and its treatment and management constitute a huge global economic burden. Currently, the main clinical treatments are not sufficient to cure kidney diseases. During its development, nanotechnology has shown unprecedented potential for application to kidney diseases. However, nanotechnology has disadvantages such as high cost and poor bioavailability. In contrast, biopolymers are not only widely available but also highly bioavailable. Therefore, biopolymer-based nanosystems offer new promising solutions for the treatment of kidney diseases. This paper reviews the biopolymer-based nanosystems that have been used for renal diseases and describes strategies for the specific, targeted delivery of drugs to the kidney as well as the physicochemical properties of the nanoparticles that affect the targeting success.
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Affiliation(s)
| | | | | | | | - Liyu He
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha 410011, China; (H.L.)
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15
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Peres RAS, Peruchetti DB, Silva-Aguiar RP, Teixeira DE, Gomes CP, Takiya CM, Pinheiro AAS, Caruso-Neves C. Rapamycin treatment induces tubular proteinuria: role of megalin-mediated protein reabsorption. Front Pharmacol 2023; 14:1194816. [PMID: 37484026 PMCID: PMC10359992 DOI: 10.3389/fphar.2023.1194816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/27/2023] [Indexed: 07/25/2023] Open
Abstract
Introduction: Rapamycin is an immunosuppressor that acts by inhibiting the serine/threonine kinase mechanistic target of rapamycin complex 1. Therapeutic use of rapamycin is limited by its adverse effects. Proteinuria is an important marker of kidney damage and a risk factor for kidney diseases progression and has been reported in patients and animal models treated with rapamycin. However, the mechanism underlying proteinuria induced by rapamycin is still an open matter. In this work, we investigated the effects of rapamycin on parameters of renal function and structure and on protein handling by proximal tubule epithelial cells (PTECs). Methods: Healthy BALB/c mice were treated with 1.5 mg/kg rapamycin by oral gavage for 1, 3, or 7 days. At the end of each treatment, the animals were kept in metabolic cages and renal function and structural parameters were analyzed. LLC-PK1 cell line was used as a model of PTECs to test specific effect of rapamycin. Results: Rapamycin treatment did not change parameters of glomerular structure and function. Conversely, there was a transient increase in 24-h proteinuria, urinary protein to creatinine ratio (UPCr), and albuminuria in the groups treated with rapamycin. In accordance with these findings, rapamycin treatment decreased albumin-fluorescein isothiocyanate uptake in the renal cortex. This effect was associated with reduced brush border expression and impaired subcellular distribution of megalin in PTECs. The effect of rapamycin seems to be specific for albumin endocytosis machinery because it did not modify renal sodium handling or (Na++K+)ATPase activity in BALB/c mice and in the LLC-PK1 cell line. A positive Pearson correlation was found between megalin expression and albumin uptake while an inverse correlation was shown between albumin uptake and UPCr or 24-h proteinuria. Despite its effect on albumin handling in PTECs, rapamycin treatment did not induce tubular injury measured by interstitial space and collagen deposition. Conclusion: These findings suggest that proteinuria induced by rapamycin could have a tubular rather than a glomerular origin. This effect involves a specific change in protein endocytosis machinery. Our results open new perspectives on understanding the undesired effect of proteinuria generated by rapamycin.
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Affiliation(s)
- Rodrigo A. S. Peres
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Diogo B. Peruchetti
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo P. Silva-Aguiar
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Douglas E. Teixeira
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carlos P. Gomes
- Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- School of Medicine and Surgery, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Christina M. Takiya
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Acacia S. Pinheiro
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Rio de Janeiro Innovation Network in Nanosystems for Health-NanoSAÚDE/FAPERJ, Rio de Janeiro, Brazil
| | - Celso Caruso-Neves
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Rio de Janeiro Innovation Network in Nanosystems for Health-NanoSAÚDE/FAPERJ, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Regenerative Medicine, Rio de Janeiro, Brazil
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16
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Rbaibi Y, Long KR, Shipman KE, Ren Q, Baty CJ, Kashlan OB, Weisz OA. Megalin, cubilin, and Dab2 drive endocytic flux in kidney proximal tubule cells. Mol Biol Cell 2023; 34:ar74. [PMID: 37126375 PMCID: PMC10295476 DOI: 10.1091/mbc.e22-11-0510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 03/27/2023] [Accepted: 04/17/2023] [Indexed: 05/02/2023] Open
Abstract
The kidney proximal tubule (PT) elaborates a uniquely high-capacity apical endocytic pathway to retrieve albumin and other proteins that escape the glomerular filtration barrier. Megalin and cubilin/amnionless (CUBAM) receptors engage Dab2 in these cells to mediate clathrin-dependent uptake of filtered ligands. Knockout of megalin or Dab2 profoundly inhibits apical endocytosis and is believed to atrophy the endocytic pathway. We generated CRISPR/Cas9 knockout (KO) clones lacking cubilin, megalin, or Dab2 expression in highly differentiated PT cells and determined the impact on albumin internalization and endocytic pathway function. KO of each component had different effects on the concentration dependence of albumin uptake as well its distribution within PT cells. Reduced uptake of a fluid phase marker was also observed, with megalin KO cells having the most dramatic decline. Surprisingly, protein levels and distribution of key endocytic proteins were preserved in KO PT cell lines and in megalin KO mice, despite the reduced endocytic activity. Our data highlight specific functions of megalin, cubilin, and Dab2 in apical endocytosis and demonstrate that these proteins drive endocytic flux without compromising the physical integrity of the apical endocytic pathway. Our studies suggest a novel model to explain how these components coordinate endocytic uptake in PT cells.
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Affiliation(s)
- Youssef Rbaibi
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Kimberly R. Long
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Katherine E. Shipman
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Qidong Ren
- School of Medicine, Tsinghua University, Beijing, China, 100084
| | - Catherine J. Baty
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Ossama B. Kashlan
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Ora A. Weisz
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
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17
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Barta P, Nachtigal P, Maixnerova J, Zemankova L, Trejtnar F. Validation of Freshly Isolated Rat Renal Cells as a Tool for Preclinical Assessment of Radiolabeled Receptor-Specific Peptide Uptake in the Kidney. Pharmaceuticals (Basel) 2023; 16:ph16050696. [PMID: 37242479 DOI: 10.3390/ph16050696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/19/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023] Open
Abstract
The synthetic analogs of regulatory peptides radiolabeled with adequate radionuclides are perspective tools in nuclear medicine. However, undesirable uptake and retention in the kidney limit their application. Specific in vitro methods are used to evaluate undesirable renal accumulation. Therefore, we investigated the usefulness of freshly isolated rat renal cells for evaluating renal cellular uptake of receptor-specific peptide analogs. Special attention was given to megalin as this transport system is an important contributor to the active renal uptake of the peptides. Freshly isolated renal cells were obtained from native rat kidneys by the collagenase method. Compounds with known accumulation in renal cells were used to verify the viability of cellular transport systems. Megalin expressions in isolated rat renal cells were compared to two other potential renal cell models by Western blotting. Specific tubular cell markers were used to confirm the presence of proximal tubular cells expressing megalin in isolated rat renal cell preparations by immunohistochemistry. Colocalization experiments on isolated rat kidney cells confirmed the presence of proximal tubular cells bearing megalin in preparations. The applicability of the method was tested by an accumulation study with several analogs of somatostatin and gastrin labeled with indium-111 or lutetium-177. Therefore, isolated rat renal cells may be an effective screening tool for in vitro analyses of renal uptake and comparative renal accumulation studies of radiolabeled peptides or other radiolabeled compounds with potential nephrotoxicity.
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Affiliation(s)
- Pavel Barta
- Department of Biophysics and Physical Chemistry, Faculty of Pharmacy in Hradec Kralové, Charles University, Akademika Heyrovskeho 1203, 50005 Hradec Kralove, Czech Republic
| | - Petr Nachtigal
- Department of Biological and Medical Sciences, Faculty of Pharmacy in Hradec Kralové, Charles University, Akademika Heyrovskeho 1203, 50005 Hradec Kralove, Czech Republic
| | - Jana Maixnerova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralové, Charles University, Akademika Heyrovskeho 1203, 50005 Hradec Kralove, Czech Republic
| | - Lenka Zemankova
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Slechtitelu 27, 78371 Olomouc, Czech Republic
| | - Frantisek Trejtnar
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralové, Charles University, Akademika Heyrovskeho 1203, 50005 Hradec Kralove, Czech Republic
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18
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Zulijani A, Milardović A, Kovač Z, Perić B, Jakovac H. Megalin Expression in Primary Oral Squamous Cell Carcinoma Is Associated with the Presence of Lymph Node Metastases, Vascular Invasion, and Lower Overall Survival. Curr Issues Mol Biol 2023; 45:2757-2766. [PMID: 37185704 PMCID: PMC10136934 DOI: 10.3390/cimb45040180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
Megalin (LRP2) is a rapidly recycling multiligand endocytic receptor primarily expressed in polarized epithelial cells. Although megalin might be involved in tumor growth and invasiveness through several mechanisms, its role has been understudied in the field of molecular oncology so far. The present study aimed to evaluate the impact of megalin expression in oral squamous cell carcinoma (OSCC) on disease progression. Megalin expression was evaluated immunohistochemically in 63 OSCC specimens. Data obtained were retrospectively compared with patient clinicopathological features and their survival. The proportion of megalin-expressing cells in the primary OSCC tissue was significantly associated with metastatic spreading to lymph nodes, vascular invasion and lower overall survival rate. Results obtained by the study suggest that megalin can be considered as a novel molecule involved in OSCC pathogenesis, but also useful as a potential biomarker for cancer progression.
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19
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Rasmussen MQ, Tindbæk G, Nielsen MM, Merrild C, Steiniche T, Pedersen JS, Moestrup SK, Degn SE, Madsen M. Epigenetic Silencing of LRP2 Is Associated with Dedifferentiation and Poor Survival in Multiple Solid Tumor Types. Cancers (Basel) 2023; 15:cancers15061830. [PMID: 36980716 PMCID: PMC10046670 DOI: 10.3390/cancers15061830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/07/2023] [Accepted: 03/09/2023] [Indexed: 03/30/2023] Open
Abstract
More than 80% of human cancers originate in epithelial tissues. Loss of epithelial cell characteristics are hallmarks of tumor development. Receptor-mediated endocytosis is a key function of absorptive epithelial cells with importance for cellular and organismal homeostasis. LRP2 (megalin) is the largest known endocytic membrane receptor and is essential for endocytosis of various ligands in specialized epithelia, including the proximal tubules of the kidney, the thyroid gland, and breast glandular epithelium. However, the role and regulation of LRP2 in cancers that arise from these tissues has not been delineated. Here, we examined the expression of LRP2 across 33 cancer types in The Cancer Genome Atlas. As expected, the highest levels of LRP2 were found in cancer types that arise from LRP2-expressing absorptive epithelial cells. However, in a subset of tumors from these cancer types, we observed epigenetic silencing of LRP2. LRP2 expression showed a strong inverse correlation to methylation of a specific CpG site (cg02361027) in the first intron of the LRP2 gene. Interestingly, low expression of LRP2 was associated with poor patient outcome in clear cell renal cell carcinoma, papillary renal cell carcinoma, mesothelioma, papillary thyroid carcinoma, and invasive breast carcinoma. Furthermore, loss of LRP2 expression was associated with dedifferentiated histological and molecular subtypes of these cancers. These observations now motivate further studies on the functional role of LRP2 in tumors of epithelial origin and the potential use of LRP2 as a cancer biomarker.
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Affiliation(s)
| | - Gitte Tindbæk
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
- Department of Clinical Biochemistry, Horsens Regional Hospital, 8700 Horsens, Denmark
| | - Morten Muhlig Nielsen
- Department of Molecular Medicine (MOMA), Aarhus University Hospital, 8200 Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark
| | - Camilla Merrild
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Torben Steiniche
- Department of Pathology, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Jakob Skou Pedersen
- Department of Molecular Medicine (MOMA), Aarhus University Hospital, 8200 Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark
- Bioinformatics Research Center (BiRC), Aarhus University, 8000 Aarhus, Denmark
| | - Søren K Moestrup
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
- Department of Cancer and Inflammation Research, University of Southern Denmark, 5230 Odense, Denmark
| | - Søren E Degn
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Mette Madsen
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
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20
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Peng Z, Wang H, Zheng J, Wang J, Xiang Y, Liu C, Ji M, Liu H, Pan L, Qin X, Qu X. Is the proximal tubule the focus of tubulointerstitial fibrosis? Heliyon 2023; 9:e13508. [PMID: 36846656 PMCID: PMC9950842 DOI: 10.1016/j.heliyon.2023.e13508] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/15/2023] [Accepted: 02/01/2023] [Indexed: 02/09/2023] Open
Abstract
Tubulointerstitial fibrosis (TIF), a common end result of almost all progressive chronic kidney diseases (CKD), is also the best predictor of kidney survival. Almost all cells in the kidney are involved in the progression of TIF. Myofibroblasts, the primary producers of extracellular matrix, have previously received a great deal of attention; however, a large body of emerging evidence reveals that proximal tubule (PT) plays a central role in TIF progression. In response to injury, renal tubular epithelial cells (TECs) transform into inflammatory and fibroblastic cells, producing various bioactive molecules that drive interstitial inflammation and fibrosis. Here we reviewed the increasing evidence for the key role of the PT in promoting TIF in tubulointerstitial and glomerular injury and discussed the therapeutic targets and carrier systems involving the PT that holds particular promise for treating patients with fibrotic nephropathy.
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Affiliation(s)
- Zhi Peng
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Hui Wang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Jiaoyun Zheng
- Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jie Wang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Yang Xiang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Chi Liu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Ming Ji
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Huijun Liu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Lang Pan
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Xiaoqun Qin
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China
| | - Xiangping Qu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410008, Hunan, China,Corresponding author.
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21
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Brandt F, Ullrich M, Wodtke J, Kopka K, Bachmann M, Löser R, Pietzsch J, Pietzsch HJ, Wodtke R. Enzymological Characterization of 64Cu-Labeled Neprilysin Substrates and Their Application for Modulating the Renal Clearance of Targeted Radiopharmaceuticals. J Med Chem 2023; 66:516-537. [PMID: 36595224 DOI: 10.1021/acs.jmedchem.2c01472] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The applicability of radioligands for targeted endoradionuclide therapy is limited due to radiation-induced toxicity to healthy tissues, in particular to the kidneys as primary organs of elimination. The targeting of enzymes of the renal brush border membrane by cleavable linkers that permit the formation of fast eliminating radionuclide-carrying cleavage fragments gains increasing interest. Herein, we synthesized a small library of 64Cu-labeled cleavable linkers and quantified their substrate potentials toward neprilysin (NEP), a highly abundant peptidase at the renal brush border membrane. This allowed for the derivation of structure-activity relationships, and selected cleavable linkers were attached to the somatostatin receptor subtype 2 ligand [Tyr3]octreotate. Radiopharmacological characterization revealed that a substrate-based targeting of NEP in the kidneys with small peptides entails their premature cleavage in the blood circulation by soluble and endothelium-derived NEP. However, for a kidney-specific targeting of NEP, the additional targeting of albumin in the blood is highlighted.
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Affiliation(s)
- Florian Brandt
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Martin Ullrich
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
| | - Johanna Wodtke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
| | - Klaus Kopka
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany.,National Center for Tumor Diseases (NCT) Dresden, University Hospital Carl Gustav Carus, Fetscherstraße 74, 01307Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, Fetscherstraße 74, 01307Dresden, Germany
| | - Michael Bachmann
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,National Center for Tumor Diseases (NCT) Dresden, University Hospital Carl Gustav Carus, Fetscherstraße 74, 01307Dresden, Germany
| | - Reik Löser
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Jens Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Hans-Jürgen Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstraße 4, 01069Dresden, Germany
| | - Robert Wodtke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328Dresden, Germany
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22
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Priante G, Ceol M, Gianesello L, Bizzotto D, Braghetta P, Calò LA, Del Prete D, Anglani F. Emerging Perspectives on the Rare Tubulopathy Dent Disease: Is Glomerular Damage a Direct Consequence of ClC-5 Dysfunction? Int J Mol Sci 2023; 24:1313. [PMID: 36674829 PMCID: PMC9864126 DOI: 10.3390/ijms24021313] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/22/2022] [Accepted: 12/24/2022] [Indexed: 01/12/2023] Open
Abstract
Dent disease (DD1) is a rare tubulopathy caused by mutations in the CLCN5 gene. Glomerulosclerosis was recently reported in DD1 patients and ClC-5 protein was shown to be expressed in human podocytes. Nephrin and actin cytoskeleton play a key role for podocyte functions and podocyte endocytosis seems to be crucial for slit diaphragm regulation. The aim of this study was to analyze whether ClC-5 loss in podocytes might be a direct consequence of the glomerular damage in DD1 patients. Three DD1 kidney biopsies presenting focal global glomerulosclerosis and four control biopsies were analyzed by immunofluorescence (IF) for nephrin and podocalyxin, and by immunohistochemistry (IHC) for ClC-5. ClC-5 resulted as down-regulated in DD1 vs. control (CTRL) biopsies in both tubular and glomerular compartments (p < 0.01). A significant down-regulation of nephrin (p < 0.01) in DD1 vs. CTRL was demonstrated. CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/Caspase9) gene editing of CLCN5 in conditionally immortalized human podocytes was used to obtain clones with the stop codon mutation p.(R34Efs*14). We showed that ClC-5 and nephrin expression, analyzed by quantitative Reverse Transcription/Polymerase Chain Reaction (qRT/PCR) and In-Cell Western (ICW), was significantly downregulated in mutant clones compared to the wild type ones. In addition, F-actin staining with fluorescent phalloidin revealed actin derangements. Our results indicate that ClC-5 loss might alter podocyte function either through cytoskeleton disorganization or through impairment of nephrin recycling.
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Affiliation(s)
- Giovanna Priante
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
| | - Monica Ceol
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
| | - Lisa Gianesello
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
| | - Dario Bizzotto
- Department of Molecular Medicine, University of Padua, 35121 Padua, Italy
| | - Paola Braghetta
- Department of Molecular Medicine, University of Padua, 35121 Padua, Italy
| | - Lorenzo Arcangelo Calò
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
| | - Dorella Del Prete
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
| | - Franca Anglani
- Kidney Histomorphology and Molecular Biology Laboratory, Nephrology Unit, Department of Medicine—DIMED, University of Padua, Via Giustiniani n° 2, 35128 Padua, Italy
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23
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Xu B, Wang C, Chen H, Zhang L, Gong L, Zhong L, Yang J. Protective role of MG53 against ischemia/reperfusion injury on multiple organs: A narrative review. Front Physiol 2022; 13:1018971. [PMID: 36479346 PMCID: PMC9720843 DOI: 10.3389/fphys.2022.1018971] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 11/07/2022] [Indexed: 12/19/2023] Open
Abstract
Ischemia/reperfusion (I/R) injury is a common clinical problem after coronary angioplasty, cardiopulmonary resuscitation, and organ transplantation, which can lead to cell damage and death. Mitsugumin 53 (MG53), also known as Trim72, is a conservative member of the TRIM family and is highly expressed in mouse skeletal and cardiac muscle, with minimal amounts in humans. MG53 has been proven to be involved in repairing cell membrane damage. It has a protective effect on I/R injury in multiple oxygen-dependent organs, such as the heart, brain, lung, kidney, and liver. Recombinant human MG53 also plays a unique role in I/R, sepsis, and other aspects, which is expected to provide new ideas for related treatment. This article briefly reviews the pathophysiology of I/R injury and how MG53 mitigates multi-organ I/R injury.
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Affiliation(s)
- Bowen Xu
- The 2nd Medical College of Binzhou Medical University, Yantai, Shandong, China
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
| | - Chunxiao Wang
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
| | - Hongping Chen
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
- Medical Department of Qingdao University, Qingdao, Shandong, China
| | - Lihui Zhang
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
- Medical Department of Qingdao University, Qingdao, Shandong, China
| | - Lei Gong
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
| | - Lin Zhong
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
| | - Jun Yang
- Department of Cardiology, Yantai Yuhuangding Hospital, Yantai, Shandong, China
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24
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Sokolova MO, Sobolev VE, Goncharov NV. Ultrastructural Changes in the Kidneys and Biochemical Parameters of Blood and Urine in Rats under Acute Intoxication with O,O-Diethyl O-(4-nitrophenyl) Phosphate. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022060084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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25
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Mitigation of Cadmium Toxicity through Modulation of the Frontline Cellular Stress Response. STRESSES 2022. [DOI: 10.3390/stresses2030025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cadmium (Cd) is an environmental toxicant of public health significance worldwide. Diet is the main Cd exposure source in the non-occupationally exposed and non-smoking populations. Metal transporters for iron (Fe), zinc (Zn), calcium (Ca), and manganese (Mn) are involved in the assimilation and distribution of Cd to cells throughout the body. Due to an extremely slow elimination rate, most Cd is retained by cells, where it exerts toxicity through its interaction with sulfur-containing ligands, notably the thiol (-SH) functional group of cysteine, glutathione, and many Zn-dependent enzymes and transcription factors. The simultaneous induction of heme oxygenase-1 and the metal-binding protein metallothionein by Cd adversely affected the cellular redox state and caused the dysregulation of Fe, Zn, and copper. Experimental data indicate that Cd causes mitochondrial dysfunction via disrupting the metal homeostasis of this organelle. The present review focuses on the adverse metabolic outcomes of chronic exposure to low-dose Cd. Current epidemiologic data indicate that chronic exposure to Cd raises the risk of type 2 diabetes by several mechanisms, such as increased oxidative stress, inflammation, adipose tissue dysfunction, increased insulin resistance, and dysregulated cellular intermediary metabolism. The cellular stress response mechanisms involving the catabolism of heme, mediated by heme oxygenase-1 and -2 (HO-1 and HO-2), may mitigate the cytotoxicity of Cd. The products of their physiologic heme degradation, bilirubin and carbon monoxide, have antioxidative, anti-inflammatory, and anti-apoptotic properties.
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26
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Satarug S, Gobe GC, Vesey DA. Multiple Targets of Toxicity in Environmental Exposure to Low-Dose Cadmium. TOXICS 2022; 10:toxics10080472. [PMID: 36006151 PMCID: PMC9412446 DOI: 10.3390/toxics10080472] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/06/2022] [Accepted: 08/12/2022] [Indexed: 05/06/2023]
Abstract
Dietary assessment reports and population surveillance programs show that chronic exposure to low levels of environmental cadmium (Cd) is inevitable for most people, and adversely impacts the health of children and adults. Based on a risk assessment model that considers an increase in the excretion of β2-microglobulin (β2M) above 300 μg/g creatinine to be the "critical" toxicity endpoint, the tolerable intake level of Cd was set at 0.83 µg/kg body weight/day, and a urinary Cd excretion rate of 5.24 µg/g creatinine was considered to be the toxicity threshold level. The aim of this review is to draw attention to the many other toxicity endpoints that are both clinically relevant and more appropriate to derive Cd exposure limits than a β2M endpoint. In the present review, we focus on a reduction in the glomerular filtration rate and diminished fecundity because chronic exposure to low-dose Cd, reflected by its excretion levels as low as 0.5 µg/g creatinine, have been associated with dose-dependent increases in risk of these pathological symptoms. Some protective effects of the nutritionally essential elements selenium and zinc are highlighted. Cd-induced mitochondrial dysfunction is discussed as a potential mechanism underlying gonadal toxicities and infertility.
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Affiliation(s)
- Soisungwan Satarug
- Kidney Disease Research Collaborative, Translational Research Institute, Brisbane 4102, Australia
- Correspondence:
| | - Glenda C. Gobe
- Kidney Disease Research Collaborative, Translational Research Institute, Brisbane 4102, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia
- NHMRC Centre of Research Excellence for CKD QLD, UQ Health Sciences, Royal Brisbane and Women’s Hospital, Brisbane 4029, Australia
| | - David A. Vesey
- Kidney Disease Research Collaborative, Translational Research Institute, Brisbane 4102, Australia
- Department of Nephrology, Princess Alexandra Hospital, Brisbane 4075, Australia
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27
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Passarella D, Ciampi S, Di Liberto V, Zuccarini M, Ronci M, Medoro A, Foderà E, Frinchi M, Mignogna D, Russo C, Porcile C. Low-Density Lipoprotein Receptor-Related Protein 8 at the Crossroad between Cancer and Neurodegeneration. Int J Mol Sci 2022; 23:ijms23168921. [PMID: 36012187 PMCID: PMC9408729 DOI: 10.3390/ijms23168921] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022] Open
Abstract
The low-density-lipoprotein receptors represent a family of pleiotropic cell surface receptors involved in lipid homeostasis, cell migration, proliferation and differentiation. The family shares common structural features but also has significant differences mainly due to tissue-specific interactors and to peculiar proteolytic processing. Among the receptors in the family, recent studies place low-density lipoprotein receptor-related protein 8 (LRP8) at the center of both neurodegenerative and cancer-related pathways. From one side, its overexpression has been highlighted in many types of cancer including breast, gastric, prostate, lung and melanoma; from the other side, LRP8 has a potential role in neurodegeneration as apolipoprotein E (ApoE) and reelin receptor, which are, respectively, the major risk factor for developing Alzheimer’s disease (AD) and the main driver of neuronal migration, and as a γ-secretase substrate, the main enzyme responsible for amyloid formation in AD. The present review analyzes the contributions of LDL receptors, specifically of LRP8, in both cancer and neurodegeneration, pointing out that depending on various interactions and peculiar processing, the receptor can contribute to both proliferative and neurodegenerative processes.
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Affiliation(s)
- Daniela Passarella
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Silvia Ciampi
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Valentina Di Liberto
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, 90133 Palermo, Italy
| | - Mariachiara Zuccarini
- Department of Medical Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy
| | - Maurizio Ronci
- Department of Pharmacy, University of Chieti-Pescara, 66100 Chieti, Italy
| | - Alessandro Medoro
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Emanuele Foderà
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Monica Frinchi
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, 90133 Palermo, Italy
| | - Donatella Mignogna
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
| | - Claudio Russo
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
- Correspondence: ; Tel.: +39-0874404897
| | - Carola Porcile
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy
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28
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TMAO Suppresses Megalin Expression and Albumin Uptake in Human Proximal Tubular Cells Via PI3K and ERK Signaling. Int J Mol Sci 2022; 23:ijms23168856. [PMID: 36012119 PMCID: PMC9407713 DOI: 10.3390/ijms23168856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/22/2022] [Accepted: 07/23/2022] [Indexed: 11/23/2022] Open
Abstract
Trimethylamine-N-oxide (TMAO) is a uremic toxin, which has been associated with chronic kidney disease (CKD). Renal tubular epithelial cells play a central role in the pathophysiology of CKD. Megalin is an albumin-binding surface receptor on tubular epithelial cells, which is indispensable for urine protein reabsorption. To date, no studies have investigated the effect of TMAO on megalin expression and the functional properties of human tubular epithelial cells. The aim of this study was first to identify the functional effect of TMAO on human renal proximal tubular cells and second, to unravel the effects of TMAO on megalin-cubilin receptor expression. We found through global gene expression analysis that TMAO was associated with kidney disease. The microarray analysis also showed that megalin expression was suppressed by TMAO, which was also validated at the gene and protein level. High glucose and TMAO was shown to downregulate megalin expression and albumin uptake similarly. We also found that TMAO suppressed megalin expression via PI3K and ERK signaling. Furthermore, we showed that candesartan, dapagliflozin and enalaprilat counteracted the suppressive effect of TMAO on megalin expression. Our results may further help us unravel the role of TMAO in CKD development and to identify new therapeutic targets to counteract TMAOs effects.
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29
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Morgan J, Yarwood R, Starborg T, Yan G, Lowe M. Pacsin2 is required for endocytosis in the zebrafish pronephric tubule. Biol Open 2022; 11:275521. [PMID: 35616009 PMCID: PMC9235069 DOI: 10.1242/bio.059150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 05/19/2022] [Indexed: 11/25/2022] Open
Abstract
Endocytosis mediates the cellular uptake of numerous molecules from the extracellular space and is a fundamentally important process. In the renal proximal tubule, the scavenger receptor megalin and its co-receptor cubilin mediate endocytosis of low molecular weight proteins from the renal filtrate. However, the extent to which megalin endocytosis relies on different components of the trafficking machinery remains relatively poorly defined in vivo. In this study, we identify a functional requirement for the F-BAR protein pacsin2 in endocytosis in the renal proximal tubule of zebrafish larvae. Pacsin2 is expressed throughout development and in all zebrafish tissues, similar to the mammalian orthologue. Within renal tubular epithelial cells, pacsin2 is enriched at the apical pole where it is localised to endocytic structures. Loss of pacsin2 results in reduced endocytosis within the proximal tubule, which is accompanied by a reduction in the abundance of megalin and endocytic organelles. Our results indicate that pacsin2 is required for efficient endocytosis in the proximal tubule, where it likely cooperates with other trafficking machinery to maintain endocytic uptake and recycling of megalin. Summary: We identify a role for the F-BAR protein pacsin2 in endocytosis in the renal tubule of zebrafish larvae.
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Affiliation(s)
- Joseph Morgan
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Rebecca Yarwood
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Tobias Starborg
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Guanhua Yan
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Martin Lowe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
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30
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Emerging Albumin-Binding Anticancer Drugs for Tumor-Targeted Drug Delivery: Current Understandings and Clinical Translation. Pharmaceutics 2022; 14:pharmaceutics14040728. [PMID: 35456562 PMCID: PMC9028280 DOI: 10.3390/pharmaceutics14040728] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/20/2022] [Accepted: 03/24/2022] [Indexed: 02/01/2023] Open
Abstract
Albumin has shown remarkable promise as a natural drug carrier by improving pharmacokinetic (PK) profiles of anticancer drugs for tumor-targeted delivery. The exogenous or endogenous albumin enhances the circulatory half-lives of anticancer drugs and passively target the tumors by the enhanced permeability and retention (EPR) effect. Thus, the albumin-based drug delivery leads to a potent antitumor efficacy in various preclinical models, and several candidates have been evaluated clinically. The most successful example is Abraxane, an exogenous human serum albumin (HSA)-bound paclitaxel formulation approved by the FDA and used to treat locally advanced or metastatic tumors. However, additional clinical translation of exogenous albumin formulations has not been approved to date because of their unexpectedly low delivery efficiency, which can increase the risk of systemic toxicity. To overcome these limitations, several prodrugs binding endogenous albumin covalently have been investigated owing to distinct advantages for a safe and more effective drug delivery. In this review, we give account of the different albumin-based drug delivery systems, from laboratory investigations to clinical applications, and their potential challenges, and the outlook for clinical translation is discussed. In addition, recent advances and progress of albumin-binding drugs to move more closely to the clinical settings are outlined.
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31
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Edwards A, Long KR, Baty CJ, Shipman KE, Weisz OA. Modeling normal and nephrotic axial uptake of albumin and other filtered proteins along the proximal tubule. J Physiol 2022; 600:1933-1952. [PMID: 35178707 PMCID: PMC9012691 DOI: 10.1113/jp282885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/10/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS We used new and published data to develop a mathematical model that predicts the profile of albumin uptake in the mouse proximal tubule (PT) in normal and nephrotic states, and partially accounts for competitive inhibition of uptake by normally filtered and pathologic ligands. Three pathways, consisting of high-affinity uptake by cubilin receptors, low-affinity uptake by megalin receptors, and fluid phase uptake, contribute to the overall retrieval of filtered proteins. The axial profile and efficiency of protein uptake depend on the initial filtrate composition and the individual protein affinities for megalin and cubilin. Under normal conditions, the majority of albumin is retrieved in S1 but shifts to S2 under nephrotic conditions. Other proteins exhibit different uptake profiles. Our model explains how tubular proteinuria can occur despite a large excess in potential PT uptake capacity. ABSTRACT Recent studies indicate that filtered albumin is retrieved in the proximal tubule (PT) via three pathways: receptor-mediated endocytosis via cubilin (high affinity) and megalin (low affinity), and fluid-phase uptake. Expression of megalin is required to maintain all three pathways, making it challenging to determine their respective contributions. Moreover, uptake of filtered molecules varies between the sub-segments (S1, S2, and S3) that make up the PT. Here we used new and published data to develop a mathematical model that predicts the rates of albumin uptake in mouse PT sub-segments in normal and nephrotic states, and partially accounts for competition by β2-microglobulin (β2m) and Immunoglobulin G (IgG). Our simulations indicate that receptor-mediated, rather than fluid-phase uptake, accounts for the vast majority of ligand recovery. Our model predicts that ∼75% of normally filtered albumin is reabsorbed via cubilin; however, megalin-mediated uptake predominates under nephrotic conditions. Our results also suggest that ∼80% of albumin is normally recovered in S1, whereas nephrotic conditions or knockout of cubilin shifts the bulk of albumin uptake to S2. The model predicts β2m and IgG axial recovery profiles qualitatively similar to those of albumin under normal conditions. In contrast with albumin however, the bulk of IgG and β2m uptake still occurs in S1 under nephrotic conditions. Overall, our model provides a kinetic rationale for why tubular proteinuria can occur even though a large excess in potential PT uptake capacity exists, and suggests testable predictions to expand our understanding of the recovery profile of filtered proteins along the PT. Abstract figure legend. Data from mouse models and from cultured proximal tubule (PT) cells were used to create a mathematical model that predicts the uptake profile of albumin and other filtered ligands along the mouse PT in normal and nephrotic states. The distinct contributions of cubilin receptors (magenta), megalin receptors (green), and fluid phase uptake (blue) to total albumin retrieval (black) in S1, S2, and S3 subsegments of the PT are delineated. Under normal conditions, albumin is primarily recovered in the S1 segment by cubilin, whereas the majority is retrieved in S2 under nephrotic conditions. Other proteins exhibit strikingly different uptake profiles. Our model explains how the distribution and capacity of high-affinity and low-affinity uptake pathways enable uptake of albumin over a broad range of filtered concentrations, and how tubular proteinuria can occur despite a large excess in potential PT uptake capacity. Created with BioRender.com. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Aurélie Edwards
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Kimberly R Long
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Catherine J Baty
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Katherine E Shipman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
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32
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Brożyna AA, Żmijewski MA, Linowiecka K, Kim TK, Slominski RM, Slominski AT. Disturbed expression of vitamin D and retinoic acid-related orphan receptors α and γ and of megalin in inflammatory skin diseases. Exp Dermatol 2022; 31:781-788. [PMID: 34995387 PMCID: PMC9064941 DOI: 10.1111/exd.14521] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 12/14/2021] [Accepted: 01/04/2022] [Indexed: 02/06/2023]
Abstract
The pathogenesis of inflammatory skin diseases is associated with the abnormal activity of keratinocytes and immune cells infiltrate. Vitamin D3 deficiency can correlate with the increased incidence, severity and duration of inflammatory skin disorders. The exact mechanism on how vitamin D3 influences inflammatory skin diseases still requires clarification. However, it can be associated with the disturbances in transmembrane glycoprotein-LRP2/megalin, which is implicated in vitamin D3 transport to the cell, and defects in vitamin D-signalling through the nuclear receptors. Therefore, by using immunohistochemistry, we analysed the expression of LRP2/megalin, VDR, RORα and RORγ in allergic contact dermatitis, lichen simplex chronicus, sarcoidosis and psoriasis in comparison with the normal skin. We observed decreased expression of LRP2/megalin in all inflammatory lesions in comparison with the normal skin. Significant differences were also noticed in VDR, RORα and RORγ levels between inflammatory lesions and normal skin. Our research indicates disturbed expression of LRP2/megalin, VDR, RORα and RORγ in inflammatory skin lesions in comparison with normal skin. Therefore, we suggest that changes in the activity of these proteins may play role in pathogenesis of inflammatory skin disorders. Furthermore, we suggest that LRP2/megalin, VDR, RORα and RORy may serve as targets in therapy of these diseases.
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Affiliation(s)
- Anna A Brożyna
- Department of Human Biology, Institute of Biology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland
| | - Michał A Żmijewski
- Faculty of Medicine, Department of Histology, Medical University of Gdańsk, Gdańsk, Poland
| | - Kinga Linowiecka
- Department of Human Biology, Institute of Biology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland
| | - Tae-Kang Kim
- Departments of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Radomir M Slominski
- Departments of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Graduate Biomedical Sciences Program, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Andrzej T Slominski
- Departments of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Laboratory Service, VA Medical Center at Birmingham, Birmingham, Alabama, USA
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33
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Yang J, Xu Y, Deng L, Zhou L, Qiu L, Zhang Y, Zhou J. CUBN gene mutations may cause focal segmental glomerulosclerosis (FSGS) in children. BMC Nephrol 2022; 23:15. [PMID: 34979989 PMCID: PMC8725476 DOI: 10.1186/s12882-021-02654-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 12/20/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Imerslund-Gräsbeck Syndrome (IGS) is mainly caused by CUBN gene biallelic mutations. Proteinuria accompanies IGS specific symptoms in about half of the patients, isolated proteinuria is rarely reported. Here we present 3 patients with isolated proteinuria and focal segmental glomerulosclerosis (FSGS) caused by CUBN gene biallelic pathogenic variants. METHOD Whole exome sequencing was performed on three children with isolated proteinuria. CUBN gene biallelic pathogenic variants were found and then verified by sanger sequencing. Their clinical, pathological and molecular genetic characteristics were analyzed and correlated accordingly. RESULTS All three children presented with isolated proteinuria, no megaloblastic anemia. Their urine levels of β2 microglobulin were normal or slightly higher. Renal biopsies showed focal segmental glomerulosclerosis with mild glomerular mesangial hypercellularity, partial effacement of foot processes and podocyte microvillation. Two of them were found to carry compound heterozygous mutations and one homozygous mutation of CUBN gene. Totally four CUBN gene biallelic pathogenic variants were identified, including c.9287 T > C (p.L3096P), c.122 + 1G > A, c.7906C > T (p.R2636*), c.10233G > A (p.W3411*). Except for intron splice-site mutation, all other variants are located in highly conserved sites of CUB domain for binding to albumin. CONCLUSION The results demonstrate that CUBN gene mutations may cause isolated proteinuria pathologically presented as FSGS. Our cases extend the spectrum of renal manifestation and genotype of CUBN gene mutations.
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Affiliation(s)
- Jing Yang
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China
| | - Yongli Xu
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China
| | - Linxia Deng
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China
| | - Luowen Zhou
- Department of Neurosurgery, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Wuhan, China
| | - Liru Qiu
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China
| | - Yu Zhang
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China
| | - Jianhua Zhou
- Department of Pediatrics, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Jiefang Ave. No. 1095, Wuhan, 430030, China.
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Atienza-Manuel A, Castillo-Mancho V, De Renzis S, Culi J, Ruiz-Gómez M. Endocytosis mediated by an atypical CUBAM complex modulates slit diaphragm dynamics in nephrocytes. Development 2021; 148:272711. [PMID: 34738617 PMCID: PMC8710305 DOI: 10.1242/dev.199894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/22/2021] [Indexed: 01/14/2023]
Abstract
The vertebrate endocytic receptor CUBAM, consisting of three cubilin monomers complexed with a single amnionless molecule, plays a major role in protein reabsorption in the renal proximal tubule. Here, we show that Drosophila CUBAM is a tripartite complex composed of Amnionless and two cubilin paralogues, Cubilin and Cubilin2, and that it is required for nephrocyte slit diaphragm (SD) dynamics. Loss of CUBAM-mediated endocytosis induces dramatic morphological changes in nephrocytes and promotes enlarged ingressions of the external membrane and SD mislocalisation. These phenotypes result in part from an imbalance between endocytosis, which is strongly impaired in CUBAM mutants, and exocytosis in these highly active cells. Of note, rescuing receptor-mediated endocytosis by Megalin/LRP2 or Rab5 expression only partially restores SD positioning in CUBAM mutants, suggesting a specific requirement of CUBAM in SD degradation and/or recycling. This finding and the reported expression of CUBAM in podocytes suggest a possible unexpected conserved role for this endocytic receptor in vertebrate SD remodelling. Summary: A genetic study revealing that endocytosis mediated by an atypical CUBAM endocytic receptor, composed of Amnionless and two Cubilin paralogues, regulates slit diaphragm remodelling in Drosophila nephrocytes.
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Affiliation(s)
- Alexandra Atienza-Manuel
- Centro de Biología Molecular Severo Ochoa, CSIC and UAM, Nicolás Cabrera 1, Cantoblanco 28049, Madrid, Spain
| | - Vicente Castillo-Mancho
- Centro de Biología Molecular Severo Ochoa, CSIC and UAM, Nicolás Cabrera 1, Cantoblanco 28049, Madrid, Spain
| | - Stefano De Renzis
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Joaquim Culi
- Centro de Biología Molecular Severo Ochoa, CSIC and UAM, Nicolás Cabrera 1, Cantoblanco 28049, Madrid, Spain
| | - Mar Ruiz-Gómez
- Centro de Biología Molecular Severo Ochoa, CSIC and UAM, Nicolás Cabrera 1, Cantoblanco 28049, Madrid, Spain
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35
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Grahammer F, Huber TB, Artunc F. Role of mTOR Signaling for Tubular Function and Disease. Physiology (Bethesda) 2021; 36:350-358. [PMID: 34514872 DOI: 10.1152/physiol.00021.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR) forms two distinct intracellular multiprotein complexes that control a multitude of intracellular processes linked to metabolism, proliferation, actin cytoskeleton, and survival. Recent studies have identified the importance of these complexes for transport regulation of ions and nutrients along the entire nephron. First reports could link altered activity of these complexes to certain disease entities, i.e. diabetic nephropathy, acute kidney injury or hyperkalemia.
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Affiliation(s)
- Florian Grahammer
- Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias B Huber
- Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ferruh Artunc
- Department of Internal Medicine, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany.,Institute of Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, University Tübingen, Tübingen, Germany.,German Center for Diabetes Research, University Tübingen, Tübingen, Germany
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36
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Wang X, Deng B, Yu M, Zeng T, Chen Y, Hu J, Wu Q, Li A. Constructing a passive targeting and long retention therapeutic nanoplatform based on water-soluble, non-toxic and highly-stable core-shell poly(amino acid) nanocomplexes. Biomater Sci 2021; 9:7065-7075. [PMID: 34590101 DOI: 10.1039/d1bm01246k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Drug delivery nanoplatforms have been applied in bioimaging, medical diagnosis, drug delivery and medical therapy. However, insolubility, toxicity, instability, nonspecific targeting and short retention of many hydrophobic drugs limit their extensive applications. Herein, we have constructed a passive targeting and long retention therapeutic nanoplatform of core-shell gefitinib/poly (ethylene glycol)-polytyrosine nanocomplexes (Gef-PY NCs). The Gef-PY NCs have good water-solubility, non-toxicity (correspond to 1/10 dosage of effective gefitinib (hydrochloride) (Gef·HCl) (normal drug administration and slow-release) and high stability (120 days, 80% drug retention at 4 or 25 °C). The core-shell Gef-PY NCs present unexpected kidney targeting and drug slow-release capacity (ca. 72 h). The good water-solubility, non-toxicity and high stability of Gef-PY NCs effectively solve the bottleneck question that Gef-based therapy could be used only in intraperitoneal injection due to its insolubility and severe toxicity. Such excellent properties (e.g., water-solubility, non-toxicity, high stability, kidney targeting and long retention) of Gef-PY NCs create their prominent anti-fibrosis capabilities, such as decreasing approximately 40% tubulointerstitial fibrosis area and 68% expression of collagen I within 7 days. This therapeutic efficacy is well-matched with that of 10 times the dosage of toxic Gef·HCl. It is very hopeful that Gef-PY NCs could realize clinical applications and such a strategy offers an effective route to design high-efficiency treatments for kidney- and tumor-related diseases.
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Affiliation(s)
- Xin Wang
- State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Guangdong Provincial Key Laboratory of Renal Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
| | - Bingqing Deng
- Nanobiological Medicine Center, Key Lab of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Meng Yu
- Nanobiological Medicine Center, Key Lab of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Tao Zeng
- State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Guangdong Provincial Key Laboratory of Renal Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
| | - Yuyu Chen
- Nanobiological Medicine Center, Key Lab of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Jianqiang Hu
- Nanobiological Medicine Center, Key Lab of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Qianqing Wu
- Nanobiological Medicine Center, Key Lab of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
| | - Aiqing Li
- State Key Laboratory of Organ Failure Research, National Clinical Research Center for Kidney Disease, Guangdong Provincial Key Laboratory of Renal Failure Research, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China.
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Wareing M, Smith CP. Iron Is Filtered by the Kidney and Is Reabsorbed by the Proximal Tubule. Front Physiol 2021; 12:740716. [PMID: 34658926 PMCID: PMC8514780 DOI: 10.3389/fphys.2021.740716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 08/30/2021] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to determine the iron (Fe) concentration profile within the lumen of the S2 renal proximal convoluted tubule (PCT) and to resolve whether this nephron segment transported Fe. To do this, we performed in vivo renal micropuncture on Wistar rats, collected PCT tubular fluid from superficial nephrons, and measured Fe concentration. The Fe concentration profile along the S2 PCT suggested significant Fe reabsorption. Proximal tubules were also microperfused in vivo with physiological solutions containing Fe and Zn, Cu, Mn, or Cd. PCTs perfused with 12μmol.l−1 55FeCl3 reabsorbed 105.2±12.7 fmol.mm−1.min−1 Fe, 435±52pmol.mm-1.min−1 Na, and 2.7±0.2nl.mm−1.min−1 water (mean ± SEM; n=19). Addition of ascorbate (1mmol.l−1) to the perfusate did not significantly alter Fe, Na, or water reabsorption. Supplementing the control perfusate with 60μmol.l−1 FeSO4 significantly decreased 55Fe uptake. Recalculating for the altered molar activity following addition of unlabeled Fe revealed a three-fold increase in Fe flux. Addition to the perfusate 12μmol.l−1 CuSO4, MnSO4, CdSO4, or ZnSO4 did not affect Fe, Na, or water flux. In conclusion, (1) in vivo, S2 PCTs of rat reabsorb Fe and (2) Fe is reabsorbed along the PCT via a pathway that is insensitive to Cu, Mn, Cd, or Zn. Together, these data demonstrate for the first time the hitherto speculated process of renal Fe filtration and subsequent tubular Fe reabsorption in a living mammal.
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Affiliation(s)
- Mark Wareing
- School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
| | - Craig P Smith
- School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
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38
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Dozio E, Massaccesi L, Corsi Romanelli MM. Glycation and Glycosylation in Cardiovascular Remodeling: Focus on Advanced Glycation End Products and O-Linked Glycosylations as Glucose-Related Pathogenetic Factors and Disease Markers. J Clin Med 2021; 10:jcm10204792. [PMID: 34682915 PMCID: PMC8539574 DOI: 10.3390/jcm10204792] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/15/2021] [Accepted: 10/16/2021] [Indexed: 02/07/2023] Open
Abstract
Glycation and glycosylation are non-enzymatic and enzymatic reactions, respectively, of glucose, glucose metabolites, and other reducing sugars with different substrates, such as proteins, lipids, and nucleic acids. Increased availability of glucose is a recognized risk factor for the onset and progression of diabetes-mellitus-associated disorders, among which cardiovascular diseases have a great impact on patient mortality. Both advanced glycation end products, the result of non-enzymatic glycation of substrates, and O-linked-N-Acetylglucosaminylation, a glycosylation reaction that is controlled by O-N-AcetylGlucosamine (GlcNAc) transferase (OGT) and O-GlcNAcase (OGA), have been shown to play a role in cardiovascular remodeling. In this review, we aim (1) to summarize the most recent data regarding the role of glycation and O-linked-N-Acetylglucosaminylation as glucose-related pathogenetic factors and disease markers in cardiovascular remodeling, and (2) to discuss potential common mechanisms linking these pathways to the dysregulation and/or loss of function of different biomolecules involved in this field.
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Affiliation(s)
- Elena Dozio
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (L.M.); (M.M.C.R.)
- Correspondence: ; Tel.: +39-02-50-315-342
| | - Luca Massaccesi
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (L.M.); (M.M.C.R.)
| | - Massimiliano Marco Corsi Romanelli
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (L.M.); (M.M.C.R.)
- Service of Laboratory Medicine1-Clinical Pathology, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy
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39
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Matsushita K, Mori K, Saritas T, Eiwaz MB, Funahashi Y, Nickerson MN, Hebert JF, Munhall AC, McCormick JA, Yanagita M, Hutchens MP. Cilastatin Ameliorates Rhabdomyolysis-induced AKI in Mice. J Am Soc Nephrol 2021; 32:2579-2594. [PMID: 34341182 PMCID: PMC8722809 DOI: 10.1681/asn.2020030263] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 06/17/2021] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Rhabdomyolysis, the destruction of skeletal muscle, is a significant cause of AKI and death in the context of natural disaster and armed conflict. Rhabdomyolysis may also initiate CKD. Development of specific pharmacologic therapy is desirable because supportive care is nearly impossible in austere environments. Myoglobin, the principal cause of rhabdomyolysis-related AKI, undergoes megalin-mediated endocytosis in proximal tubule cells, a process that specifically injures these cells. METHODS To investigate whether megalin is protective in a mouse model of rhabdomyolysis-induced AKI, we used male C57BL/6 mice and mice (14-32 weeks old) with proximal tubule-specific deletion of megalin. We used a well-characterized rhabdomyolysis model, injection of 50% glycerol in normal saline preceded by water deprivation. RESULTS Inducible proximal tubule-specific deletion of megalin was highly protective in this mouse model of rhabdomyolysis-induced AKI. The megalin knockout mice demonstrated preserved GFR, reduced proximal tubule injury (as indicated by kidney injury molecule-1), and reduced renal apoptosis 24 hours after injury. These effects were accompanied by increased urinary myoglobin clearance. Unlike littermate controls, the megalin-deficient mice also did not develop progressive GFR decline and persistent new proteinuria. Administration of the pharmacologic megalin inhibitor cilastatin to wild-type mice recapitulated the renoprotective effects of megalin deletion. This cilastatin-mediated renoprotective effect was dependent on megalin. Cilastatin administration caused selective proteinuria and inhibition of tubular myoglobin uptake similar to that caused by megalin deletion. CONCLUSIONS We conclude that megalin plays a critical role in rhabdomyolysis-induced AKI, and megalin interference and inhibition ameliorate rhabdomyolysis-induced AKI. Further investigation of megalin inhibition may inform translational investigation of a novel potential therapy.
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Affiliation(s)
- Katsuyuki Matsushita
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - Kiyoshi Mori
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Turgay Saritas
- Division of Nephrology & Hypertension, Oregon Health & Science University, Portland, Oregon,Division of Nephrology & Hypertension, University Hospital RWTH Aachen, Aachen, Germany
| | - Mahaba B. Eiwaz
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - Yoshio Funahashi
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - Megan N. Nickerson
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - Jessica F. Hebert
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - Adam C. Munhall
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon
| | - James A. McCormick
- Division of Nephrology & Hypertension, Oregon Health & Science University, Portland, Oregon
| | - Motoko Yanagita
- Department of Nephrology, Kyoto University Graduate School of Medicine, Kyoto, Japan,Institute for Advanced Study of Human Biology, Kyoto University, Kyoto, Japan
| | - Michael P. Hutchens
- Anesthesiology & Perioperative Medicine, Oregon Health & Science University, Portland, Oregon,Portland Veterans Affairs Medical Center, Operative Care Division, Portland, Oregon,Correspondence: Dr. Michael P. Hutchens, Operative Care Division, Portland Veterans Affairs Medical Center R&D, 5 3710 SW US Veterans Hospital Road, Portland, OR 97239.
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40
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Molecular determinants of protein reabsorption in the amphibian kidneys. Acta Histochem 2021; 123:151760. [PMID: 34303296 DOI: 10.1016/j.acthis.2021.151760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/28/2021] [Accepted: 07/11/2021] [Indexed: 11/23/2022]
Abstract
Participation of molecular determinants of endocytosis in the processes of glomerular filtration and tubular reabsorption of albumin and lysozyme in the mesonephros of grass frogs (Rana temporaria L.), lake frogs (Rana ridibunda P.), and newts (Triturus vulgaris L.) is investigated. In all studied species, the constitutive expression of endocytic receptors in proximal tubule (PT) cells is established using immunofluorescence microscopy and immunoblotting. The certain stages of lysozyme and albumin endocytosis involving megalin/LRP2, cubilin, clathrin and protein Rab11 are detailed, and the central role of ligand-induced megalin/LRP2 activity in this process is shown. Increased ligand-induced expression for clathrin and Rab11was also found. In grass frogs, the different patterns of endocytic receptors and both absorbed proteins in the initial parts of proximal tubules suggest the proximo-distal specialization of absorptive processes along these tubule segments, similar to this in more complex mammalian nephrons. This data, as well as the revealed peculiarities of ligand-receptor interactions during intracellular trafficking of proteins prove that megalin is mainly involved in the absorption of lysozyme. At the same time, albumin absorption is mediated by both receptors, or cubilin contributes the most. The detection of endocytic receptor in glomerular structural elements in frogs and newts suggests the participation of filtration barrier components in endocytosis of filterable proteins. The results represent a new contribution to the study of the fundamental mechanisms of renal protein uptake in the amphibian mesonephros as a more primitive kidney compared to mammalian metanephros.
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41
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Menè P, Moioli A, Stoppacciaro A, Lai S, Festuccia F. Acute Kidney Injury in Monoclonal Gammopathies. J Clin Med 2021; 10:jcm10173871. [PMID: 34501317 PMCID: PMC8432219 DOI: 10.3390/jcm10173871] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 01/07/2023] Open
Abstract
Monoclonal gammopathies (MG) encompass a variety of disorders related to clonal expansion and/or malignant transformation of B lymphocytes. Deposition of free immunoglobulin (Ig) components (light or heavy chains, LC/HC) within the kidney during MG may result over time in multiple types and degrees of injury, including acute kidney injury (AKI). AKI is generally a consequence of tubular obstruction by luminal aggregates of LC, a pattern known as “cast nephropathy”. Monoclonal Ig LC can also be found as intracellular crystals in glomerular podocytes or proximal tubular cells. Proliferative glomerulonephritis with monoclonal Ig deposits is another, less frequent form of kidney injury with a sizable impact on renal function. Hypercalcemia (in turn related to bone reabsorption triggered by proliferating plasmacytoid B cells) may lead to AKI via functional mechanisms. Pharmacologic treatment of MG may also result in additional renal injury due to local toxicity or the tumor lysis syndrome. The present review focuses on AKI complicating MG, evaluating predictors, risk factors, mechanisms of damage, prognosis, and options for treatment.
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Affiliation(s)
- Paolo Menè
- Department of Clinical and Molecular Medicine, “Sapienza” University of Rome, 00189 Rome, Italy
- Division of Nephrology, Sant’Andrea University Hospital, Via di Grottarossa 1035-1039, 00189 Rome, Italy; (A.M.); (F.F.)
- Correspondence: ; Tel.: +39-(06)-3377-5949
| | - Alessandra Moioli
- Division of Nephrology, Sant’Andrea University Hospital, Via di Grottarossa 1035-1039, 00189 Rome, Italy; (A.M.); (F.F.)
| | - Antonella Stoppacciaro
- Division of Pathology, Department of Clinical and Molecular Medicine, “Sapienza” University of Rome, 00189 Rome, Italy;
| | - Silvia Lai
- Division of Nephrology, Department of Translational and Precision Medicine, “Sapienza” University of Rome, 00161 Rome, Italy;
| | - Francescaromana Festuccia
- Division of Nephrology, Sant’Andrea University Hospital, Via di Grottarossa 1035-1039, 00189 Rome, Italy; (A.M.); (F.F.)
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Kawakami R, Matsui M, Konno A, Kaneko R, Shrestha S, Shrestha S, Sunaga H, Hanaoka H, Goto S, Hosojima M, Kabasawa H, Obokata M, Koitabashi N, Matsui H, Sasaki T, Saito A, Yanagita M, Hirai H, Kurabayashi M, Iso T. Urinary FABP1 is a biomarker for impaired proximal tubular protein reabsorption and is synergistically enhanced by concurrent liver injury. J Pathol 2021; 255:362-373. [PMID: 34370295 PMCID: PMC9292749 DOI: 10.1002/path.5775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/28/2021] [Accepted: 08/04/2021] [Indexed: 11/09/2022]
Abstract
Urinary fatty acid binding protein 1 (FABP1, also known as liver‐type FABP) has been implicated as a biomarker of acute kidney injury (AKI) in humans. However, the precise biological mechanisms underlying its elevation remain elusive. Here, we show that urinary FABP1 primarily reflects impaired protein reabsorption in proximal tubule epithelial cells (PTECs). Bilateral nephrectomy resulted in a marked increase in serum FABP1 levels, suggesting that the kidney is an essential organ for removing serum FABP1. Injected recombinant FABP1 was filtered through the glomeruli and robustly reabsorbed via the apical membrane of PTECs. Urinary FABP1 was significantly elevated in mice devoid of megalin, a giant endocytic receptor for protein reabsorption. Elevation of urinary FABP1 was also observed in patients with Dent disease, a rare genetic disease characterized by defective megalin function in PTECs. Urinary FABP1 levels were exponentially increased following acetaminophen overdose, with both nephrotoxicity and hepatotoxicity observed. FABP1‐deficient mice with liver‐specific overexpression of FABP1 showed a massive increase in urinary FABP1 levels upon acetaminophen injection, indicating that urinary FABP1 is liver‐derived. Lastly, we employed transgenic mice expressing diphtheria toxin receptor (DT‐R) either in a hepatocyte‐ or in a PTEC‐specific manner, or both. Upon administration of diphtheria toxin (DT), massive excretion of urinary FABP1 was induced in mice with both kidney and liver injury, while mice with either injury type showed marginal excretion. Collectively, our data demonstrated that intact PTECs have a considerable capacity to reabsorb liver‐derived FABP1 through a megalin‐mediated mechanism. Thus, urinary FABP1, which is synergistically enhanced by concurrent liver injury, is a biomarker for impaired protein reabsorption in AKI. These findings address the use of urinary FABP1 as a biomarker of histologically injured PTECs that secrete FABP1 into primary urine, and suggest the use of this biomarker to simultaneously monitor impaired tubular reabsorption and liver function. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Ryo Kawakami
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Miki Matsui
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Ayumu Konno
- Department of Neurophysiology and Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Japan.,Viral Vector Core, Gunma University Initiative for Advanced Research (GIAR), Maebashi, Japan
| | - Ryosuke Kaneko
- Bioresource Center, Gunma University Graduate School of Medicine, Maebashi, Japan.,KOKORO-Biology Group, Laboratories for Integrated Biology, Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Shreya Shrestha
- Department of Nephrology and Rheumatology, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Suman Shrestha
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Hiroaki Sunaga
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan.,Center for Liberal Arts and Sciences, Ashikaga University, Ashikaga, Japan
| | - Hirofumi Hanaoka
- Department of Bioimaging Information Analysis, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Sawako Goto
- Department of Applied Molecular Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Michihiro Hosojima
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Hideyuki Kabasawa
- Department of Clinical Nutrition Science, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Masaru Obokata
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Norimichi Koitabashi
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Hiroki Matsui
- Department of Laboratory Sciences, Gunma University Graduate School of Health Sciences, Maebashi, Japan
| | - Tsutomu Sasaki
- Laboratory of Nutrition Chemistry, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Akihiko Saito
- Department of Applied Molecular Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Motoko Yanagita
- Department of Nephrology, Graduate School of Medicine, Kyoto, Japan.,Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto, Japan
| | - Hirokazu Hirai
- Department of Neurophysiology and Neural Repair, Gunma University Graduate School of Medicine, Maebashi, Japan.,Viral Vector Core, Gunma University Initiative for Advanced Research (GIAR), Maebashi, Japan
| | - Masahiko Kurabayashi
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Tatsuya Iso
- Department of Cardiovascular Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan.,Department of Medical Technology and Clinical Engineering, Faculty of Medical Technology and Clinical Engineering, Gunma University of Health and Welfare, Maebashi, Japan
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43
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Bgatova N, Taskaeva I, Makarova V. Influence of distant tumor growth and lithium treatment on ultrastructural organization of kidney proximal tubules. Ultrastruct Pathol 2021; 45:212-223. [PMID: 34304707 DOI: 10.1080/01913123.2021.1954735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Tumor growth causes significant metabolic disturbances, tissue damage and the accumulation of toxic metabolites in the blood. The kidney is an organ with highly developed capillary network and therefore can be exposed to toxic metabolites. Here, the proximal renal tubule cells were studied by immunohistochemistry and electron microscopy, on a model of hepatocellular carcinoma-29 growth in the thigh of CBA mice and lithium carbonate treatment. An increase of autophagy markers (LC3 and LAMP-1) expression was revealed under conditions of distant tumor growth and especially after lithium carbonate treatment. Under conditions of distant tumor we found decrease of numerical density of endosomes and dense apical tubules in the apical part of the cells. In the perinuclear cell compartment, there were swelling of mitochondria and a decrease in their cristae, a decrease of volume density of rough endoplasmic reticulum and the presence of autophagosomes and autolysosomes. The use of lithium carbonate led to an increase of autophagic structures volume density and of dense apical tubules numerical density in the proximal tubule cells. It is possible that the activation of autophagy by lithium can promote an increase in protein recycling in the proximal tubule cells.
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Affiliation(s)
- Nataliya Bgatova
- Laboratory of Ultrastructural Research, Research Institute of Clinical and Experimental Lymphology - Branch of the Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Iuliia Taskaeva
- Laboratory of Ultrastructural Research, Research Institute of Clinical and Experimental Lymphology - Branch of the Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Viktoriia Makarova
- Laboratory of Ultrastructural Research, Research Institute of Clinical and Experimental Lymphology - Branch of the Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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44
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Weisz OA. Endocytic adaptation to functional demand by the kidney proximal tubule. J Physiol 2021; 599:3437-3446. [PMID: 34036593 DOI: 10.1113/jp281599] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/06/2021] [Indexed: 12/28/2022] Open
Abstract
The kidney proximal tubule (PT) efficiently recovers the low level of albumin and other proteins that normally escape the glomerular filtration barrier. Two large receptors, megalin and cubilin/amnionless (CUBAM), bind to and efficiently retrieve these predominantly low molecular-weight proteins via clathrin-mediated endocytosis. Studies in cell culture models suggest that PT cells may sense changes in shear stress to modulate recovery of filtered proteins in response to normal variations in filtration rate. Impairments in PT endocytic function lead to the excretion of filtered proteins into the urine (tubular proteinuria). Remarkably, when the glomerular filtration barrier is breached, the PT is able to recover excess albumin with a capacity that is orders of magnitude higher than normal. What mediates this excess capacity for albumin uptake under nephrotic conditions, and why doesn't it compensate to prevent tubular proteinuria? Here we propose an integrated new working model to describe the PT recovery of filtered proteins under normal and nephrotic states. We hypothesize that uptake via the fluid phase provides excess capacity to recover high concentrations of filtered proteins under nephrotic conditions. Further, concentration of tubular fluid along the tubule axis will enhance the efficiency of uptake in more distal regions of the PT. By contrast to cells where fluid phase and receptor-mediated uptake are independent pathways, expression of megalin is required to maintain apical endocytic pathway integrity and is essential for both uptake mechanisms. This model accounts for both the high-affinity and the high-capacity responses to filtration load in physiological and pathological states.
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Affiliation(s)
- Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
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45
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Giani JF, Veiras LC, Shen JZY, Bernstein EA, Cao D, Okwan-Duodu D, Khan Z, Gonzalez-Villalobos RA, Bernstein KE. Novel roles of the renal angiotensin-converting enzyme. Mol Cell Endocrinol 2021; 529:111257. [PMID: 33781839 PMCID: PMC8127398 DOI: 10.1016/j.mce.2021.111257] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 02/03/2021] [Accepted: 03/20/2021] [Indexed: 12/14/2022]
Abstract
The observation that all components of the renin angiotensin system (RAS) are expressed in the kidney and the fact that intratubular angiotensin (Ang) II levels greatly exceed the plasma concentration suggest that the synthesis of renal Ang II occurs independently of the circulating RAS. One of the main components of this so-called intrarenal RAS is angiotensin-converting enzyme (ACE). Although the role of ACE in renal disease is demonstrated by the therapeutic effectiveness of ACE inhibitors in treating several conditions, the exact contribution of intrarenal versus systemic ACE in renal disease remains unknown. Using genetically modified mouse models, our group demonstrated that renal ACE plays a key role in the development of several forms of hypertension. Specifically, although ACE is expressed in different cell types within the kidney, its expression in renal proximal tubular cells is essential for the development of high blood pressure. Besides hypertension, ACE is involved in several other renal diseases such as diabetic kidney disease, or acute kidney injury even when blood pressure is normal. In addition, studies suggest that ACE might mediate at least part of its effect through mechanisms that are independent of the Ang I conversion into Ang II and involve other substrates such as N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), Ang-(1-7), and bradykinin, among others. In this review, we summarize the recent advances in understanding the contribution of intrarenal ACE to different pathological conditions and provide insight into the many roles of ACE besides the well-known synthesis of Ang II.
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Affiliation(s)
- Jorge F Giani
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Luciana C Veiras
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Justin Z Y Shen
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ellen A Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - DuoYao Cao
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Derick Okwan-Duodu
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Zakir Khan
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | - Kenneth E Bernstein
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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46
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Mohammad G, Matakidou A, Robbins PA, Lakhal-Littleton S. The kidney hepcidin/ferroportin axis controls iron reabsorption and determines the magnitude of kidney and systemic iron overload. Kidney Int 2021; 100:559-569. [PMID: 33991530 PMCID: PMC8456337 DOI: 10.1016/j.kint.2021.04.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 04/15/2021] [Accepted: 04/22/2021] [Indexed: 12/21/2022]
Abstract
The hepcidin/ferroportin axis controls systemic iron homeostasis by regulating iron acquisition from the duodenum and reticuloendothelial system, respective sites of iron absorption and recycling. Ferroportin is also abundant in the kidney, where it has been implicated in tubular iron reabsorption. However, it remains unknown whether endogenous hepcidin regulates ferroportin-mediated iron reabsorption under physiological conditions, and whether such regulation is important for kidney and/or systemic iron homeostasis. To address these questions, we generated a novel mouse model with an inducible kidney-tubule specific knock-in of fpnC326Y, which encodes a hepcidin-resistant ferroportin termed FPNC326Y. Under conditions of normal iron availability, female mice harboring this allele had consistently decreased kidney iron but only transiently increased systemic iron indices. Under conditions of excess iron availability, male and female mice harboring this allele had milder kidney iron overload, but greater systemic iron overload relative to controls. Additionally, despite comparable systemic iron overload, kidney iron overload occurred in wild type mice fed an iron-loaded diet but not in hemochromatosis mice harboring a ubiquitous knock-in of fpnC326Y. Thus, our study demonstrates that endogenous hepcidin controls ferroportin-mediated tubular iron reabsorption under physiological conditions. It also shows that such control is important for both kidney and systemic iron homeostasis in the context of iron overload.
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Affiliation(s)
- Goran Mohammad
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Athena Matakidou
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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47
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Bryniarski MA, Zhao B, Chaves LD, Mikkelsen JH, Yee BM, Yacoub R, Shen S, Madsen M, Morris ME. Immunoglobulin G Is a Novel Substrate for the Endocytic Protein Megalin. AAPS JOURNAL 2021; 23:40. [PMID: 33677748 DOI: 10.1208/s12248-021-00557-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/07/2021] [Indexed: 11/30/2022]
Abstract
Therapeutic immunoglobulin G (IgG) antibodies comprise the largest class of protein therapeutics. Several factors that influence their overall disposition have been well-characterized, including target-mediated mechanics and convective flow. What remains poorly defined is the potential for non-targeted entry into various tissues or cell types by means of uptake via cell surface receptors at those sites. Megalin and cubilin are large endocytic receptors whose cooperative function plays important physiological roles at the tissues in which they are expressed. One such example is the kidney, where loss of either results in significant declines in proximal tubule protein reabsorption. Due to their diverse ligand profile and broad tissue expression, megalin and cubilin represent potential candidates for receptor-mediated uptake of IgG into various epithelia. Therefore, the objective of the current work was to determine if IgG was a novel ligand of megalin and/or cubilin. Direct binding was measured for human IgG with both megalin and the cubilin/amnionless complex. Additional work focusing on the megalin-IgG interaction was then conducted to build upon these findings. Cell uptake studies using megalin ligands for competitive inhibition or proximal tubule cells stably transduced with megalin-targeted shRNA constructs supported a role for megalin in the endocytosis of human IgG. Furthermore, a pharmacokinetic study using transgenic mice with a kidney-specific mosaic knockout of megalin demonstrated increased urinary excretion of human IgG in megalin knockout mice when compared to wild-type controls. These findings indicate that megalin is capable of binding and internalizing IgG via a high affinity interaction.
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Affiliation(s)
- Mark A Bryniarski
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA
| | - Bei Zhao
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA
| | - Lee D Chaves
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA.,Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | | | - Benjamin M Yee
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA
| | - Rabi Yacoub
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Shichen Shen
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA
| | - Mette Madsen
- Department of Biomedicine, Aarhus University, 8000, Aarhus C., Denmark
| | - Marilyn E Morris
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, 445 Pharmacy Building, Buffalo, New York, 14214-8033, USA.
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48
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Charlton JR, Tan W, Daouk G, Teot L, Rosen S, Bennett KM, Cwiek A, Nam S, Emma F, Jouret F, Oliveira JP, Tranebjærg L, Frykholm C, Mane S, Hildebrandt F, Srivastava T, Storm T, Christensen EI, Nielsen R. Beyond the tubule: pathological variants of LRP2, encoding the megalin receptor, result in glomerular loss and early progressive chronic kidney disease. Am J Physiol Renal Physiol 2020; 319:F988-F999. [PMID: 33103447 DOI: 10.1152/ajprenal.00295.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pathogenic variants in the LRP2 gene, encoding the multiligand receptor megalin, cause a rare autosomal recessive syndrome: Donnai-Barrow/Facio-Oculo-Acoustico-Renal (DB/FOAR) syndrome. Because of the rarity of the syndrome, the long-term consequences of the tubulopathy on human renal health have been difficult to ascertain, and the human clinical condition has hitherto been characterized as a benign tubular condition with asymptomatic low-molecular-weight proteinuria. We investigated renal function and morphology in a murine model of DB/FOAR syndrome and in patients with DB/FOAR. We analyzed glomerular filtration rate in mice by FITC-inulin clearance and clinically characterized six families, including nine patients with DB/FOAR and nine family members. Urine samples from patients were analyzed by Western blot analysis and biopsy materials were analyzed by histology. In the mouse model, we used histological methods to assess nephrogenesis and postnatal renal structure and contrast-enhanced magnetic resonance imaging to assess glomerular number. In megalin-deficient mice, we found a lower glomerular filtration rate and an increase in the abundance of injury markers, such as kidney injury molecule-1 and N-acetyl-β-d-glucosaminidase. Renal injury was validated in patients, who presented with increased urinary kidney injury molecule-1, classical markers of chronic kidney disease, and glomerular proteinuria early in life. Megalin-deficient mice had normal nephrogenesis, but they had 19% fewer nephrons in early adulthood and an increased fraction of nephrons with disconnected glomerulotubular junction. In conclusion, megalin dysfunction, as present in DB/FOAR syndrome, confers an increased risk of progression into chronic kidney disease.
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Affiliation(s)
- Jennifer R Charlton
- Division of Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, Virginia
| | - Weizhen Tan
- Division of Nephrology, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Ghaleb Daouk
- Division of Nephrology, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Lisa Teot
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts
| | - Seymour Rosen
- Department of Pathology, Boston Children's Hospital, Boston, Massachusetts.,Department of Pathology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Kevin M Bennett
- Department of Radiology, Washington University in Saint Louis, St. Louis, Missouri
| | - Aleksandra Cwiek
- Division of Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, Virginia
| | - Sejin Nam
- Department of Physics, University of Hawai'i at Manoa, Manoa, Hawai'i
| | - Francesco Emma
- Division of Nephrology, Department of Pediatric Subspecialties, Bambino Gesù Children's Hospital- Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - François Jouret
- Groupe Interdisciplinaire de Génoprotéomique Appliquée, Unit of Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - João Paulo Oliveira
- Service of Medical Genetics, São João University Hospital Centre and Faculty of Medicine, University of Porto and i3S-Institute for Health Research and Innovation, Porto, Portugal
| | - Lisbeth Tranebjærg
- Department of Clinical Genetics, Rigshospitalet/The Kennedy Centre, Copenhagen, Denmark.,Institute of Clinical Medicine, University of Copenhagen, The Panum Institute, Copenhagen, Denmark
| | - Carina Frykholm
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Tina Storm
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Rikke Nielsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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49
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Jakovac H, Stašić N, Krašević M, Jonjić N, Radošević-Stašić B. Expression profiles of metallothionein-I/II and megalin/LRP-2 in uterine cervical squamous lesions. Virchows Arch 2020; 478:735-746. [PMID: 33084977 PMCID: PMC7990851 DOI: 10.1007/s00428-020-02947-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/18/2020] [Accepted: 10/09/2020] [Indexed: 12/29/2022]
Abstract
Metallothioneins (MTs) are phylogenetically old cysteine-rich proteins, which are implicated in a variety of physiological and pathological processes. Their growth-regulating, anti-apoptotic and anti-inflammatory functions have been attributed not only to intracellular free radical scavenging and to zinc and copper regulation but also to the ability of secreted MT to bind on surface lipoprotein receptor-megalin/LRP2, which enables the endocytosis of MT-I/II and a wide range of other functionally distinct ligands. In the present study, we analysed the expression pattern of both proteins in 55 cases of premalignant transformation of cervical squamous cells, i.e. in low- and high-grade squamous intraepithelial lesion (LSIL and HSIL). The data showed that in LSIL (cervical intraepithelial neoplasia CIN1; N = 25) MTs were present only in basal and parabasal cells and that megalin was only weakly expressed. In HSIL (CIN2; N = 15 and CIN 3/carcinoma in situ; N = 15), however, overexpression and co-localization of MT with megalin were found in the entire hyperplastic epithelium. Moreover, megalin immunoreactivity appeared on the glandular epithelium and vascular endothelium, as well as on lymphatic cells in stroma. Besides, multiple megalin-positive cells expressed phosphorylated Akt1, implying that MT- and/or megalin-dependent prosurvival signal transduction pathways might contribute to the development of severe cervical dysplasia. The data emphasize the diagnostic power of combined MT/megalin analysis in pre-cancer screening.
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Affiliation(s)
- Hrvoje Jakovac
- Department of Physiology and Immunology, Medical Faculty, University of Rijeka, B. Branchetta 20, 51 000 Rijeka, Croatia
| | - Nikola Stašić
- Teaching Institute of Public Health, Primorsko-goranska County, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Maja Krašević
- Department of Pathology, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Nives Jonjić
- Department of Pathology, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Biserka Radošević-Stašić
- Department of Physiology and Immunology, Medical Faculty, University of Rijeka, B. Branchetta 20, 51 000 Rijeka, Croatia
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50
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Gomes JR, Lobo A, Nogueira R, Terceiro AF, Costelha S, Lopes IM, Magalhães A, Summavielle T, Saraiva MJ. Neuronal megalin mediates synaptic plasticity-a novel mechanism underlying intellectual disabilities in megalin gene pathologies. Brain Commun 2020; 2:fcaa135. [PMID: 33225275 PMCID: PMC7667529 DOI: 10.1093/braincomms/fcaa135] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 12/15/2022] Open
Abstract
Donnai-Barrow syndrome, a genetic disorder associated to LRP2 (low-density lipoprotein receptor 2/megalin) mutations, is characterized by unexplained neurological symptoms and intellectual deficits. Megalin is a multifunctional endocytic clearance cell-surface receptor, mostly described in epithelial cells. This receptor is also expressed in the CNS, mainly in neurons, being involved in neurite outgrowth and neuroprotective mechanisms. Yet, the mechanisms involved in the regulation of megalin in the CNS are poorly understood. Using transthyretin knockout mice, a megalin ligand, we found that transthyretin positively regulates neuronal megalin levels in different CNS areas, particularly in the hippocampus. Transthyretin is even able to rescue megalin downregulation in transthyretin knockout hippocampal neuronal cultures, in a positive feedback mechanism via megalin. Importantly, transthyretin activates a regulated intracellular proteolysis mechanism of neuronal megalin, producing an intracellular domain, which is translocated to the nucleus, unveiling megalin C-terminal as a potential transcription factor, able to regulate gene expression. We unveil that neuronal megalin reduction affects physiological neuronal activity, leading to decreased neurite number, length and branching, and increasing neuronal susceptibility to a toxic insult. Finally, we unravel a new unexpected role of megalin in synaptic plasticity, by promoting the formation and maturation of dendritic spines, and contributing for the establishment of active synapses, both in in vitro and in vivo hippocampal neurons. Moreover, these structural and synaptic roles of megalin impact on learning and memory mechanisms, since megalin heterozygous mice show hippocampal-related memory and learning deficits in several behaviour tests. Altogether, we unveil a complete novel role of megalin in the physiological neuronal activity, mainly in synaptic plasticity with impact in learning and memory. Importantly, we contribute to disclose the molecular mechanisms underlying the cognitive and intellectual disabilities related to megalin gene pathologies.
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Affiliation(s)
- João R Gomes
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Andrea Lobo
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Renata Nogueira
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Ana F Terceiro
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Susete Costelha
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Igor M Lopes
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Ana Magalhães
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Teresa Summavielle
- I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,Addiction Biology Group, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal
| | - Maria J Saraiva
- Molecular Neurobiology Unit, IBMC- Instituto de Biologia Molecular e Celular, 4200-135 Porto, Portugal.,I3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
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